Renormalizable Non-Covariant Gauges and Coulomb Gauge Limit
Baulieu, L
1999-01-01
To study ``physical'' gauges such as the Coulomb, light-cone, axial or temporal gauge, we consider ``interpolating'' gauges which interpolate linearly between a covariant gauge, such as the Feynman or Landau gauge, and a physical gauge. Lorentz breaking by the gauge-fixing term of interpolating gauges is controlled by extending the BRST method to include not only the local gauge group, but also the global Lorentz group. We enumerate the possible divergences of interpolating gauges, and show that they are renormalizable, and we show that the expectation value of physical observables is the same as in a covariant gauge. In the second part of the article we study the Coulomb-gauge as the singular limit of the Landau-Coulomb interpolating gauge. We find that unrenormalized and renormalized correlation functions are finite in this limit. We also find that there are finite two-loop diagrams of ``unphysical'' particles that are not present in formal canonical quantization in the Coulomb gauge. We verify that in the ...
International Nuclear Information System (INIS)
Greensite, J.; Olejnik, S.
2003-01-01
We study the phase structure of SU(2) gauge theories at zero and high temperature, with and without scalar matter fields, in terms of the symmetric/broken realization of the remnant gauge symmetry which exists after fixing to Coulomb gauge. The symmetric realization is associated with a linearly rising color Coulomb potential (which we compute numerically), and is a necessary but not sufficient condition for confinement.
Perturbative ambiguities in Coulomb gauge QCD
International Nuclear Information System (INIS)
Doust, P.
1987-01-01
The naive Coulomb gauge Feynman rules in non-abelian gauge theory give rise to ambiguous integrals, in addition to the usual ultraviolet divergences. Generalizing the work of Cheng and Tsai, these ambiguities are resolved to all orders in perturbation theory, by defining a gauge that interpolates smoothly between the Feynman gauge and the Coulomb gauge. The extra terms V 1 +V 2 of Christ and Lee are identified with certain two-loop ambiguous terms. However, there still seem to be unsolved problems connected with renormalisation. copyright 1987 Academic Press, Inc
Asymptotic freedom in the axial and Coulomb gauges
International Nuclear Information System (INIS)
Frenkel, J.; Taylor, J.C.
1976-01-01
The sources of the negative contribution to the charge renormalization factor gsup(B)/g-1 in Yang-Mills theories are investigated in the axial and Coulomb gauges. In the axial gauge, a Kaellen dispersion relation exists but the spectral function is not positive definite because of the prescription that is used to integrate the singular polarization vectors. In the Coulomb gauge, the negative contributions are (to the lowest order) isolated in the Coulomb self-energy corrections to the Coulomb field. (Auth.)
Dimensional regularization and renormalization of Coulomb gauge quantum electrodynamics
International Nuclear Information System (INIS)
Heckathorn, D.
1979-01-01
Quantum electrodynamics is renormalized in the Coulomb gauge with covariant counter terms and without momentum-dependent wave-function renormalization constants. It is shown how to dimensionally regularize non-covariant integrals occurring in this guage, and prove that the 'minimal' subtraction prescription excludes non-covariant counter terms. Motivated by the need for a renormalized Coulomb gauge formalism in certain practical calculations, the author introduces a convenient prescription with physical parameters. The renormalization group equations for the Coulomb gauge are derived. (Auth.)
Vacuum structure of the SU(3) gauge field theory in the Coulomb gauge
International Nuclear Information System (INIS)
Yee, J.H.; Viswanathan, K.S.
1978-01-01
The SU(3) gauge field is studied in the Coulomb gauge. The Gribov ambiguities arising in the Coulomb gauge are analysed. Restricting to a class of spherically symmetric vacua it is shown that there exist non-trivial vacua characterized by a topological number eta=0, +-1/2, and +-2. This must be contrasted with the spherically symmetric SU(2) vacua which are characterized by eta=0, +-1/2. (Auth.)
Gauge orbits and the Coulomb potential
International Nuclear Information System (INIS)
Greensite, J.
2009-01-01
If the color Coulomb potential is confining, then the Coulomb field energy of an isolated color charge is infinite on an infinite lattice, even if the usual UV divergence is lattice regulated. A simple criterion for Coulomb confinement is that the expectation value of timelike link variables vanishes in the Coulomb gauge, but it is unclear how this criterion is related to the spectrum of the corresponding Faddeev-Popov operator, which can be used to formulate a quite different criterion for Coulomb confinement. The purpose of this article is to connect the two seemingly different Coulomb confinement criteria, and explain the geometrical basis of the connection.
Yang-Mills theory in Coulomb gauge; Yang-Mills-theorie in Coulombeichung
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Feuchter, C.
2006-07-01
In this thesis we study the Yang-Mills vacuum structure by using the functional Schroedinger picture in Coulomb gauge. In particular we discuss the scenario of colour confinement, which was originally formulated by Gribov. After a short introduction, we recall some basic aspects of Yang-Mills theories, its canonical quantization in the Weyl gauge and the functional Schroedinger picture. We then consider the minimal Coulomb gauge and the Gribov problem of the gauge theory. The gauge fixing of the Coulomb gauge is done by using the Faddeev-Popov method, which enables the resolution of the Gauss law - the constraint on physical states. In the third chapter, we variationally solve the stationary Yang-Mills Schroedinger equation in Coulomb gauge for the vacuum state. Therefor we use a vacuum wave functional, which is strongly peaked at the Gribov horizon. The vacuum energy functional is calculated and minimized resulting in a set of coupled Schwinger-Dyson equations for the gluon energy, the ghost and Coulomb form factors and the curvature in gauge orbit space. Using the angular approximation these integral equations have been solved analytically in both the infrared and the ultraviolet regime. The asymptotic analytic solutions in the infrared and ultraviolet regime are reasonably well reproduced by the full numerical solutions of the coupled Schwinger-Dyson equations. In the fourth chapter, we investigate the dependence of the Yang-Mills wave functional in Coulomb gauge on the Faddeev-Popov determinant. (orig.)
Generalized Coulomb gauge without Gribov ambiguity
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Fachin, S.; Parrinello, C. (New York Univ., NY (United States). Physics Dept.)
1992-05-01
We discuss a global gauge-fixing prescription that is free of the Gribov problem, preserves reflection positivity and contains as a limiting case the (maximal) Coulomb gauge. In such a formalism it is very easy to check that only color singlet states propagate in Euclidean time, for any value of [beta]. (orig.).
Two-dimensional QCD in the Coulomb gauge
International Nuclear Information System (INIS)
Kalashnikova, Yu.S.; Nefed'ev, A.V.
2002-01-01
Various aspects of the 't Hooft model for two-dimensional QCD in the limit of infinite number of colours in the Coulomb gauge are discussed. The properties of mesonic excitations are studied, with special emphasis on the pion. Attention is paid to the dual role of the pion. which, while a genuine qq-bar state, is a Goldstone boson of two-dimensional QCD as well. In particular, the validity of the soft-pion theorems is demonstrated. It is shown that the Coulomb gauge is the most suitable choice for the study of hadronic observables involving pions [ru
Questions of quark confinement and ambiguities in Coulomb gauge of Yang-Mills fields
International Nuclear Information System (INIS)
Abarbanel, H.D.I.; Bartels, J.
1978-01-01
The ambiguities considered by Gribov in the formulation of Coulomb gauge in non-Abelian gauge theories are discussed and the division of gauge field space into a sector with a unique transverse gauge, a sector with a two-fold ambiguity in transverse gauge, etc. is reviewed. The authors argue in a semi-classical fashion that transitions between these sectors readily occur and discuss the connection with ideas of quark confinement in Coulomb gauge. Because of these transitions it appears that the functional integral formulation of Coulomb gauge will be rather more complicated than expected in the past. (Auth.)
Spectral sum for the color-Coulomb potential in SU(3) Coulomb gauge lattice Yang-Mills theory
International Nuclear Information System (INIS)
Nakagawa, Y.; Nakamura, A.; Saito, T.; Toki, H.
2010-01-01
We discuss the essential role of the low-lying eigenmodes of the Faddeev-Popov (FP) ghost operator on the confining color-Coulomb potential using SU(3) quenched lattice simulations in the Coulomb gauge. The color-Coulomb potential is expressed as a spectral sum of the FP ghost operator and has been explored by partially summing the FP eigenmodes. We take into account the Gribov copy effects that have a great impact on the FP eigenvalues and the color-Coulomb potential. We observe that the lowest eigenvalue vanishes in the thermodynamic limit much faster than that in the Landau gauge. The color-Coulomb potential at large distances is governed by the near-zero FP eigenmodes; in particular, the lowest one accounts for a substantial portion of the color-Coulomb string tension comparable to the Wilson string tension.
Hamiltonian approach to 1 + 1 dimensional Yang-Mills theory in Coulomb gauge
International Nuclear Information System (INIS)
Reinhardt, H.; Schleifenbaum, W.
2009-01-01
We study the Hamiltonian approach to 1 + 1 dimensional Yang-Mills theory in Coulomb gauge, considering both the pure Coulomb gauge and the gauge where in addition the remaining constant gauge field is restricted to the Cartan algebra. We evaluate the corresponding Faddeev-Popov determinants, resolve Gauss' law and derive the Hamiltonians, which differ in both gauges due to additional zero modes of the Faddeev-Popov kernel in the pure Coulomb gauge. By Gauss' law the zero modes of the Faddeev-Popov kernel constrain the physical wave functionals to zero colour charge states. We solve the Schroedinger equation in the pure Coulomb gauge and determine the vacuum wave functional. The gluon and ghost propagators and the static colour Coulomb potential are calculated in the first Gribov region as well as in the fundamental modular region, and Gribov copy effects are studied. We explicitly demonstrate that the Dyson-Schwinger equations do not specify the Gribov region while the propagators and vertices do depend on the Gribov region chosen. In this sense, the Dyson-Schwinger equations alone do not provide the full non-abelian quantum gauge theory, but subsidiary conditions must be required. Implications of Gribov copy effects for lattice calculations of the infrared behaviour of gauge-fixed propagators are discussed. We compute the ghost-gluon vertex and provide a sensible truncation of Dyson-Schwinger equations. Approximations of the variational approach to the 3 + 1 dimensional theory are checked by comparison to the 1 + 1 dimensional case
The three-point function in split dimensional regularization in the Coulomb gauge
Leibbrandt, G
1998-01-01
We use a gauge-invariant regularization procedure, called ``split dimensional regularization'', to evaluate the quark self-energy $\\Sigma (p)$ and quark-quark-gluon vertex function $\\Lambda_\\mu (p^\\prime,p)$ in the Coulomb gauge, $\\vec{\\bigtriangledown}\\cdot\\vec{A}^a = 0$. The technique of split dimensional regularization was designed to regulate Coulomb-gauge Feynman integrals in non-Abelian theories. The technique which is based on two complex regulating parameters, $\\omega$ and $\\sigma$, is shown to generate a well-defined set of Coulomb-gauge integrals. A major component of this project deals with the evaluation of four-propagator and five-propagator Coulomb integrals, some of which are nonlocal. It is further argued that the standard one-loop BRST identity relating $\\Sigma$ and $\\Lambda_\\mu$, should by rights be replaced by a more general BRST identity which contains two additional contributions from ghost vertex diagrams. Despite the appearance of nonlocal Coulomb integrals, both $\\Sigma$ and $\\Lambda_\\...
The three-point function in split dimensional regularization in the Coulomb gauge
International Nuclear Information System (INIS)
Leibbrandt, G.
1998-01-01
We use a gauge-invariant regularization procedure, called split dimensional regularization, to evaluate the quark self-energy Σ(p) and quark-quark-gluon vertex function Λ μ (p',p) in the Coulomb gauge, ∇-vector.A - vectora=0. The technique of split dimensional regularization was designed to regulate Coulomb-gauge Feynman integrals in non-Abelian theories. The technique which is based on two complex regulating parameters, ω and σ, is shown to generate a well-defined set of Coulomb-gauge integrals. A major component of this project deals with the evaluation of four-propagator and five-propagator Coulomb integrals, some of which are non-local. It is further argued that the standard one-loop BRST identity relating Σ and Λ μ , should by rights be replaced by a more general BRST identity which contains two additional contributions from ghost vertex diagrams. Despite the appearance of non-local Coulomb integrals, both Σ and Λ μ are local functions which satisfy the appropriate BRST identity. Application of split dimensional regularization to two-loop energy integrals is briefly discussed. (orig.)
The Yang-Mills vacuum wave functional in Coulomb gauge
International Nuclear Information System (INIS)
Campagnari, Davide R.
2011-01-01
Yang-Mills theories are the building blocks of today's Standard Model of elementary particle physics. Besides methods based on a discretization of space-time (lattice gauge theory), also analytic methods are feasible, either in the Lagrangian or in the Hamiltonian formulation of the theory. This thesis focuses on the Hamiltonian approach to Yang-Mills theories in Coulomb gauge. The thesis is presented in cumulative form. After an introduction into the general formulation of Yang-Mills theories, the Hamilton operator in Coulomb gauge is derived. Chap. 1 deals with the heat-kernel expansion of the Faddeev-Popov determinant. In Chapters 2 and 3, the high-energy behaviour of the theory is investigated. To this purpose, perturbative methods are applied, and the results are compared with the ones stemming from functional methods in Coulomb and Landau gauge. Chap. 4 is devoted to the variational approach. Variational ansatzes going beyond the Gaussian form for the vacuum wave functional are considered and treated using Dyson-Schwinger techniques. Equations for the higher-order variational kernels are derived and their effects are estimated. Chap. 5 presents an application of the previously obtained propagators, namely the evaluation of the topological susceptibility, which is related to the mass of the η meson. Finally, a short overview of the perturbative treatment of dynamical fermion fields is presented.
Ice limit of Coulomb gauge Yang-Mills theory
International Nuclear Information System (INIS)
Heinzl, T.; Ilderton, A.; Langfeld, K.; Lavelle, M.; McMullan, D.
2008-01-01
In this paper we describe gauge invariant multiquark states generalizing the path integral framework developed by Parrinello, Jona-Lasinio, and Zwanziger to amend the Faddeev-Popov approach. This allows us to produce states such that, in a limit which we call the ice limit, fermions are dressed with glue exclusively from the fundamental modular region associated with Coulomb gauge. The limit can be taken analytically without difficulties, avoiding the Gribov problem. This is illustrated by an unambiguous construction of gauge invariant mesonic states for which we simulate the static quark-antiquark potential.
Quasineutral Limit of the Schrödinger-Poisson System in Coulomb Gauge
Lin, Chi-Kun; Wong, Yau-Shu; Wu, Kung-Chien
2012-01-01
The zero Debye length asymptotic of the Schrödinger-Poisson system in Coulomb gauge for ill-prepared initial data is studied. We prove that when the scaled Debye length λ → 0, the current density defined by the solution of the Schrödinger-Poisson system in the Coulomb gauge converges to the solution of the rotating incompressible Euler equation plus a fast singular oscillating gradient vector field.
Canfora, Fabrizio; Giacomini, Alex; Oliva, Julio
2010-08-01
It is shown that on curved backgrounds, the Coulomb gauge Faddeev-Popov operator can have zero modes even in the Abelian case. These zero modes cannot be eliminated by restricting the path integral over a certain region in the space of gauge potentials. The conditions for the existence of these zero modes are studied for static spherically symmetric spacetimes in arbitrary dimensions. For this class of metrics, the general analytic expression of the metric components in terms of the zero modes is constructed. Such expression allows one to find the asymptotic behavior of background metrics, which induce zero modes in the Coulomb gauge, an interesting example being the three-dimensional anti-de Sitter spacetime. Some of the implications for quantum field theory on curved spacetimes are discussed.
Maxwell-Chern-Simons theory in covariant and Coulomb gauges
International Nuclear Information System (INIS)
Haller, K.; Lim-Lombridas, E.
1996-01-01
We quantize quantum electrodynamics in 2 + 1 dimensions coupled to a Chern-Simons (CS) term and a charged spinor field, in covariant gauges and in the Coulomb gauge. The resulting Maxwell-Chern-Simons (MCS) theory describes charged fermions interacting with each other and with topologically massive propagating photons. We impose Gauss's law and the gauge conditions and investigate their effect on the dynamics and on the statistics of n-particle states. We construct charged spinor states that obey Gauss's law and the gauge conditions and transform the theory to representations in which these states constitute a Fock space. We demonstrate that, in these representations, the nonlocal interactions between charges and between charges and transverse currents-along with the interactions between currents and massive propagating photons-are identical in the different gauges we analyze in this and in earlier work. We construct the generators of the Poincare group, show that they implement the Poincare algebra, and explicitly demonstrate the effect of rotations and Lorentz boosts on the particle states. We show that the imposition of Gauss's law does not produce any open-quotes exoticclose quotes fractional statistics. In the case of the covariant gauges, this demonstration makes use of unitary transformations that provide charged particles with the gauge fields required by Gauss's law, but that leave the anticommutator algebra of the spinor fields untransformed. In the Coulomb gauge, we show that the anticommutators of the spinor fields apply to the Dirac-Bergmann constraint surfaces, on which Gauss's law and the gauge conditions obtain. We examine MCS theory in the large CS coupling constant limit, and compare that limiting form with CS theory, in which the Maxwell kinetic energy term is not included in the Larangian. 34 refs
A further pathology of the Coulomb gauge in non-Abelian Yang-Mills theories
International Nuclear Information System (INIS)
Ademollo, M.; Napolitano, E.; Sciuto, S.
1978-01-01
In the first part the vacuum structure of SU(2) Yang-Mills theories in the Coulomb gauge is discussed. It is proved that the only transverse pure gauge field Asub(μ)(x) = U -1 deltasub(μ)U with U(x) → (as r→infinity) const., is the trivial one Asub(μ)(x) equivalent to 0; the features of other possible vacua with U(x) → (as r→infinity) U(theta, pli) are studied. In the second part, regular Euclidean configurations that connect a vacuum state at x 4 = -infinity to another at x 4 = +infinity are discussed. It is proved, always working in the Coulomb gauge, that the perturbative vacuum Asub(μ)(x) equivalent to 0 cannot tunnel into any other one and that regular configurations with non-vanishing Pontryagin number q cannot affect such a vacuum. Moreover, strong arguments are given to show that many-instanton configurations (mod(q)>=2) cannot be expressed at all in the Coulomb gauge, that is by a regular field Asub(μ) satisfying the transversality condition deltasub(i)Asub(i) (x, x 4 ) = 0. (Auth.)
Monopole operators and Hilbert series of Coulomb branches of 3 d = 4 gauge theories
Cremonesi, Stefano; Hanany, Amihay; Zaffaroni, Alberto
2014-01-01
This paper addresses a long standing problem - to identify the chiral ring and moduli space (i.e. as an algebraic variety) on the Coulomb branch of an = 4 superconformal field theory in 2+1 dimensions. Previous techniques involved a computation of the metric on the moduli space and/or mirror symmetry. These methods are limited to sufficiently small moduli spaces, with enough symmetry, or to Higgs branches of sufficiently small gauge theories. We introduce a simple formula for the Hilbert series of the Coulomb branch, which applies to any good or ugly three-dimensional = 4 gauge theory. The formula counts monopole operators which are dressed by classical operators, the Casimir invariants of the residual gauge group that is left unbroken by the magnetic flux. We apply our formula to several classes of gauge theories. Along the way we make various tests of mirror symmetry, successfully comparing the Hilbert series of the Coulomb branch with the Hilbert series of the Higgs branch of the mirror theory.
Aspects of confinement in a functional approach to coulomb gauge QCD
International Nuclear Information System (INIS)
Lichtenegger, K. G.
2010-01-01
The topic of this thesis are aspects of the confinement phenomenon in Coulomb gauge Quantum Chromodynamics.First we investigated the quark gap equation with an infrared-divergent Coulomb gluon propagator D00. As an extension to studies performed so far, some forms of an infrared-divergent spatial quark-gluon vertex have been tested, but the results remain inconclusive. There is, however, considerable evidence that some infrared dressing is required in order to obtain quantitatively reliable results. The numerical studies performed in this thesis indicate that neither the vertex form derived from the approximate Abelian Ward-Takahashi identity nor a globally divergent vertex is fit for this purpose.In addition, finite-temperature studies of pure gauge theory have been performed: On the one hand the Gribov-Zwanziger approach has been extended to the deconfined phase of Yang-Mills theory. The resulting equation has been solved numerically, which yields the Gribov mass. From this, the free energy, the interaction measure and the bulk viscosity have been determined. On the other hand, the asymptotic infrared behaviour of Dyson-Schwinger equations in Coulomb gauge have been analyzed. They yield a more than linearly rising potential for three spatial dimensions. A result which has yet to be understood.Apart from the two main topics, this thesis contains a pedagogic presentation of some peculiarities of non-Abelian gauge theories and several smaller conjectures and findings: This includes a proposal to systematize the set of gauges by introduction of an approriate metric, a discussion of the role of interpolating gauges and the use of to non-integrable potentials as well as a general expression for the number of components in the tensor decomposition of arbitrary Green functions. (author) [de
A preliminary study of the Gribov ambiguity in lattice SU(3) Coulomb gauge
Energy Technology Data Exchange (ETDEWEB)
Parrinello, C. (Physics Dept., New York Univ., NY (United States)); Petrarca, S. (Dipt. di Fisica, Rome-1 Univ. (Italy) INFN, Rome (Italy)); Vladikas, A. (Dipt. di Fisica, Rome-2 Univ. (Italy) INFN, Rome (Italy))
1991-10-10
We report on simulations of pure SU(3) gauge theory on a 10{sup 3}x20 lattice at {beta}=6.0 in the Coulomb gauge, from which the Gribov ambiguity appears to be maximal, in the sense that the gauge-fixing process is highly unstable with respect to variations of the starting configuration via random gauge transformations. We give a heuristic explanation of the larger number of Gribov copies in such a gauge with respect to the Landau gauge. (orig.).
The ghost propagator in Coulomb gauge
International Nuclear Information System (INIS)
Watson, P.; Reinhardt, H.
2011-01-01
We present results for a numerical study of the ghost propagator in Coulomb gauge whereby lattice results for the spatial gluon propagator are used as input to solving the ghost Dyson-Schwinger equation. We show that in order to solve completely, the ghost equation must be supplemented by a boundary condition (the value of the inverse ghost propagator dressing function at zero momentum) which determines if the solution is critical (zero value for the boundary condition) or subcritical (finite value). The various solutions exhibit a characteristic behavior where all curves follow the same (critical) solution when going from high to low momenta until 'forced' to freeze out in the infrared to the value of the boundary condition. The boundary condition can be interpreted in terms of the Gribov gauge-fixing ambiguity; we also demonstrate that this is not connected to the renormalization. Further, the connection to the temporal gluon propagator and the infrared slavery picture of confinement is discussed.
Localizing gauge fields on a topological Abelian string and the Coulomb law
International Nuclear Information System (INIS)
Torrealba S, Rafael S.
2010-01-01
The confinement of electromagnetic field is studied in axial symmetrical, warped, six-dimensional brane world, using a recently proposed topological Abelian string-vortex solution as background. It was found, that the massless gauge field fluctuations follow four-dimensional Maxwell equations in the Lorenz gauge. The massless zero mode is localized when the thickness of the string vortex is less than 5β/4πe 2 v 2 and there are no other localized massless modes. There is also an infinite of nonlocalized massive Fourier modes, that follow four-dimensional Proca equations with a continuous spectrum. To compute the corrections to the Coulomb potential, a radial cutoff was introduced, in order to achieve a discrete mass spectrum. As a main result, a (R o /βR 2 ) correction was found for the four-dimensional effective Coulomb law; the result is in correspondence with the observed behavior of the Coulomb potential at today's measurable distances.
Many-Body Coulomb Gauge Exotic and Charmed Hybrids
Llanes-Estrada, Felipe J.; Cotanch, Stephen R.
2000-01-01
Utilizing a QCD Coulomb gauge Hamiltonian with linear confinement specified by lattice, we report a relativistic many-body calculation for the light exotic and charmed hybrid mesons. The Hamiltonian successfully describes both quark and gluon sectors, with vacuum and quasiparticle properties generated by a BCS transformation and more elaborate TDA and RPA diagonalizations for the meson ($q\\bar{q}$) and glueball ($gg$) masses. Hybrids entail a computationally intense relativistic three quasipa...
Coulomb branches for rank 2 gauge groups in 3dN=4 gauge theories
Energy Technology Data Exchange (ETDEWEB)
Hanany, Amihay [Theoretical Physics Group, Imperial College London,Prince Consort Road, London, SW7 2AZ (United Kingdom); Sperling, Marcus [Institut für Theoretische Physik, Leibniz Universität Hannover,Appelstraße 2, 30167 Hannover (Germany)
2016-08-02
The Coulomb branch of 3-dimensional N=4 gauge theories is the space of bare and dressed BPS monopole operators. We utilise the conformal dimension to define a fan which, upon intersection with the weight lattice of a GNO-dual group, gives rise to a collection of semi-groups. It turns out that the unique Hilbert bases of these semi-groups are a sufficient, finite set of monopole operators which generate the entire chiral ring. Moreover, the knowledge of the properties of the minimal generators is enough to compute the Hilbert series explicitly. The techniques of this paper allow an efficient evaluation of the Hilbert series for general rank gauge groups. As an application, we provide various examples for all rank two gauge groups to demonstrate the novel interpretation.
Infrared behavior of the Faddeev-Popov operator in Coulomb gauge QCD
International Nuclear Information System (INIS)
Nakagawa, Y.; Saito, T.; Toki, H.; Nakamura, A.
2007-01-01
We calculate the eigenvalue distribution of the Faddeev-Popov operator in Coulomb gauge QCD using quenched SU(3) lattice simulation. In the confinement phase, the density of the low-lying eigenvalues increases with lattice volume, and the confinement criterion is satisfied. Moreover, even in the deconfinement phase, the behavior of the FP eigenvalue density is qualitatively the same as in the confinement phase. This is consistent with the fact that the color-Coulomb potential is not screened in the deconfined phase
International Nuclear Information System (INIS)
Namgung, W.
1991-01-01
The well known requirement that physical theories should be gauge independent is not so apparent in the actual calculation of gauge theories, especially in the perturbative approach. In this paper the authors show that the Weyl, Coulomb, and unitary gauges of the scalar QED are manifestly equivalent in the context of the functional Schrodinger picture. Further, the three gauge conditions are shown equivalent to the covariant gauge in the way that they correspond to some specific cases of the latter
A short proof that the Coulomb-gauge potentials yield the retarded fields
Energy Technology Data Exchange (ETDEWEB)
Heras, Jose A, E-mail: herasgomez@gmail.co [Universidad Autonoma Metropolitana, Unidad Azcapotzalco, Av. San Pablo No. 180, Col. Reynosa, Mexico D. F. 02200 (Mexico)
2011-01-15
A short demonstration that the potentials in the Coulomb gauge yield the retarded electric and magnetic fields is presented. This demonstration is relatively simple and can be presented in an advanced undergraduate course of electromagnetic theory.
A short proof that the Coulomb-gauge potentials yield the retarded fields
International Nuclear Information System (INIS)
Heras, Jose A
2011-01-01
A short demonstration that the potentials in the Coulomb gauge yield the retarded electric and magnetic fields is presented. This demonstration is relatively simple and can be presented in an advanced undergraduate course of electromagnetic theory.
International Nuclear Information System (INIS)
Wundt, B.J.; Jentschura, U.D.
2012-01-01
We investigate the coupling of the electromagnetic sources (charge and current densities) to the scalar and vector potentials in classical electrodynamics, using Green function techniques. As is well known, the scalar potential shows an action-at-a-distance behavior in Coulomb gauge. The conundrum generated by the instantaneous interaction has intrigued physicists for a long time. Starting from the differential equations that couple the sources to the potentials, we here show in a concise derivation, using the retarded Green function, how the instantaneous interaction cancels in the calculation of the electric field. The time derivative of a specific additional term in the vector potential, present only in Coulomb gauge, yields a supplementary contribution to the electric field which cancels the gradient of the instantaneous Coulomb gauge scalar potential, as required by gauge invariance. This completely eliminates the contribution of the instantaneous interaction from the electric field. It turns out that a careful formulation of the retarded Green function, inspired by field theory, is required in order to correctly treat boundary terms in partial integrations. Finally, compact integral representations are derived for the Liénard–Wiechert potentials (scalar and vector) in Coulomb gauge which manifestly contain two compensating action-at-a-distance terms. - Highlights: ► We investigate action-at-a-distance effects in electrodynamics in detail. ► We calculate the instantaneous interactions for scalar and vector potentials. ► The cancellation mechanism involves the retarded Green function. ► The mechanism is confirmed on the example of moving point charges. ► The Green function has to be treated with care for nontrivial boundary terms.
Hamiltonian approach to QCD in Coulomb gauge at zero and finite temperature
Directory of Open Access Journals (Sweden)
Reinhardt H.
2017-01-01
Full Text Available I report on recent results obtained within the Hamiltonian approach to QCD in Coulomb gauge. By relating the Gribov confinement scenario to the center vortex picture of confinement it is shown that the Coulomb string tension is tied to the spatial string tension. For the quark sector a vacuum wave functional is used which results in variational equations which are free of ultraviolet divergences. The variational approach is extended to finite temperatures by compactifying a spatial dimension. For the chiral and deconfinement phase transition pseudo-critical temperatures of 170MeV and 198 MeV, respectively, are obtained.
Yuji, NAKAWAKI; Azuma, TANAKA; Kazuhiko, OZAKI; Division of Physics and Mathematics, Faculty of Engineering Setsunan University; Junior College of Osaka Institute of Technology; Faculty of General Education, Osaka Institute of Technology
1994-01-01
Gauge Equivalence of the A_3=0 (axial) gauge to the Coulomb gauge is directly verified in QED. For that purpose a pair of conjugate zero-norm fields are introduced. This enables us to construct a canonical formulation in the axial gauge embedded in the indefinite metric Hilbert space in such a way that the Feynman rules are not altered. In the indefinite metric Hilbert space we can implement a gauge transformation, which otherwise has to be carried out only by hand, as main parts of a canonic...
Energy Technology Data Exchange (ETDEWEB)
Anon.
2001-03-01
The new CINEMAXX cinema building in the Trier city centre has fully glazed walls and a modern air conditioning system. The system was installed by local organisations. Its key components are two Comer-Dorin screw compressors. [German] Im Trierer Stadtzentrum befindet sich ein neues CINEMAXX-Kino, hinter dessen glaeserner Fassade die Klimaanlage diskret verborgen bleibt. Oertliche Firmen der Branche konnten die Ausschreibung der Klimaanlage zu ihren Gunsten entscheiden und mit Erfahrung und handwerklichem Koennen unter Verwendung zweier Comer-Dorin-Schraubenverdichter eine nachahmenswerte Loesung planen und installieren. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Brugger, H. [Siemens AG, Vienna (Austria). Bereich Energieuebertragung und -verteilung; Nobach, U. [Siemens AG, Nuernberg (Germany). Bereich Energieuebertragung und -verteilung; Hoenes, R.; Vetter, T. [Neckarwerke Stuttgart AG (Germany)
1999-04-19
Liberalization of the energy market gives new requirements to the organization of the departments of utilities and their IT-solutions. The authors explain by using the example of the new energy management system for Neckarwerke Stuttgart AG, how a modern Data Warehouse-platform is created for the operative and economic tasks for electricity supply and district heating in a competitive market. (orig.) [Deutsch] Aufgrund der Liberalisierung des Strommarktes erwachsen bei den Energieversorgungsunternehmen neue Anforderungen an die Organisation der Geschaeftsbereiche und an die EDV-Hilfsmittel. Die Verfasser erlaeutern am Beispiel des neuen Energiemanagementsystems fuer die Neckarwerke Stuttgart AG wie mit einem modernen Data Warehouse die Plattform fuer die Loesung der operativen und der wirtschaftlichen Aufgaben der Strom- und Fernwaermebeschaffung in einem Wettbewerbsumfeld geschaffen werden kann. (orig.)
Wahlberg, Nanna; Madsen, Anders Ø; Mikkelsen, Kurt V
2018-06-09
The nucleation processes of acetaminophen on poly(methyl methacrylate) and poly(vinyl acetate) have been investigated and the mechanisms of the processes are studied. This is achieved by a combination of theoretical models and computational investigations within the framework of a modified QM/MM method; a Coulomb-van der Waals model. We have combined quantum mechanical computations and electrostatic models at the atomistic level for investigating the stability of different orientations of acetaminophen on the polymer surfaces. Based on the Coulomb-van der Waals model, we have determined the most stable orientation to be a flat orientation, and the strongest interaction is seen between poly(vinyl acetate) and the molecule in a flat orientation in vacuum.
Energy Technology Data Exchange (ETDEWEB)
Svigler, J.; Vimmr, J. [Westboehmische Univ. Pilsen (Czechoslovakia). Lehrstuhl fuer Mechanik
2000-07-01
A fast development of the screw machines leads to the investigation of the physical processes, which take place in the work space of the screw machine and in the gaps on its boundary. These processes have a great influence on the performance of the screw machine especially with regard to its efficiency, therefore its knowledge is very important. It is necessary to turn our attention to the fluid dynamics of the screw machines. This paper deals with the preliminary analysis of the fluid flow in the screw machines. In this paper numerical computation of the compressible inviscid fluid flow in the work space of the screw machines and through the sealing gaps which are situated between the stator and the head of the female rotor tooth, is presented. The mathematical model of two- and three-dimensional inviscid compressible flow is described by the conservative system of the Euler equations. This problem was solved by the cell-centred finite volume method on a structured quadrilateral mesh. (orig.) [German] Die schnelle Entwicklung der Schraubenmaschinen fuehrt zur Notwendigkeit einer Untersuchung der physikalischen Vorgaenge, die im Arbeitsraum und in den arbeitsraumbegrenzenden Spalten der Schraubenmaschine ablaufen. Diese Vorgaenge beeinflussen nachhaltig das Betriebsverhalten sowie die Energiewandlungsguete, womit deren Kenntnis und der Information ueber die Details eine ausserordentliche Bedeutung zukommt. Einen Ausgangspunkt fuer die Analyse stellen die Kenntnisse im Bereich der kompressiblen Fluide dar. Der Zustand kann vor allem durch das Geschwindigkeits-, Druck-, und Temperaturfeld beurteilt werden. Der Beitrag beschaeftigt sich mit der Problematik der Stroemungsuntersuchungen des Gases im Arbeitsraum der Schaubenmaschine und im Gehaeusespalt. Die Aufgabe wird dreidimensional behandelt und auf eine Art und Weise formuliert, dass sie die Voraussetzung fuer die Erstellung eines raeumlichen Modells und der damit gekoppelten mathematischen Loesung schafft. Die
Chiral-symmetry restoration at finite densities in Coulomb-gauge QCD
International Nuclear Information System (INIS)
Kocic, A.
1986-01-01
Using the Schwinger-Dyson equation in the Hartree-Fock approximation, we show that, within a potential model motivated by the QCD Hamiltonian in the Coulomb gauge, chiral symmetry is restored at finite densities. Two cases are studied: a delta-function potential and a linear confining potential. For the former case the phase diagram is obtained analytically, whereas for the latter case numerical techniques are used. The values of physical quantities calculated for the linear confining model are consistently smaller than the experimental ones indicating that a potential with additional short-range attraction is needed to describe the quark interaction in the high-density regime
Coulomb branches with complex singularities
Argyres, Philip C.; Martone, Mario
2018-06-01
We construct 4d superconformal field theories (SCFTs) whose Coulomb branches have singular complex structures. This implies, in particular, that their Coulomb branch coordinate rings are not freely generated. Our construction also gives examples of distinct SCFTs which have identical moduli space (Coulomb, Higgs, and mixed branch) geometries. These SCFTs thus provide an interesting arena in which to test the relationship between moduli space geometries and conformal field theory data. We construct these SCFTs by gauging certain discrete global symmetries of N = 4 superYang-Mills (sYM) theories. In the simplest cases, these discrete symmetries are outer automorphisms of the sYM gauge group, and so these theories have lagrangian descriptions as N = 4 sYM theories with disconnected gauge groups.
Energy Technology Data Exchange (ETDEWEB)
Paul, A.
1999-03-01
The city of Altenburg intended to reduce the investment, energy and operating cost of administrative buildings and schools. Apart from economically efficient power supply, emission reduction was another declared goal. This was achieved by integrated heat supply system and a centralized DDC facility management system. The solution combines high availability with user-friendliness, and the systems reflect the latest state of the art. [Deutsch] Die Stadt Altenburg suchte Wege, die Investitions-, Energie- und Betriebskosten fuer Verwaltungsgebaeude und Schulen zu senken. Neben der wirtschaftlichen Waermeversorgung war ein weiteres Ziel, die hohen Emissionswerte, besonders im inneren Stadtgebiet zu mindern. Die realisierten Waermeverbundsysteme und die zentrale DDC-Gebaeudeleittechnik der Stadt Altenburg gewaehrleisten dies. Die Loesung sichert ausserdem eine hohe Versorgungssicherheit mit Anwendungskomfort. Die Anpassung der Systeme an den jeweiligen Stand der Umweltanforderung und der Technik sind sehr gut gegeben. (orig./MSK)
Coulomb string tension, asymptotic string tension, and the gluon chain
Greensite, Jeff; Szczepaniak, Adam P.
2014-01-01
We compute, via numerical simulations, the non-perturbative Coulomb potential of pure SU(3) gauge theory in Coulomb gauge. We find that that the Coulomb potential scales nicely in accordance with asymptotic freedom, that the Coulomb potential is linear in the infrared, and that the Coulomb string tension is about four times larger than the asymptotic string tension. We explain how it is possible that the asymptotic string tension can be lower than the Coulomb string tension by a factor of four.
Hamiltonian approach to QCD in Coulomb gauge: From the vacuum to finite temperatures
Directory of Open Access Journals (Sweden)
Reinhardt H.
2016-01-01
Full Text Available The variational Hamiltonian approach to QCD in Coulomb gauge is reviewedand the essential results obtained in recent years are summarized. First the results for thevacuum sector are discussed, with a special emphasis on the mechansim of confinementand chiral symmetry breaking. Then the deconfinement phase transition is described byintroducing temperature in the Hamiltonian approach via compactification of one spatialdimension. The effective action for the Polyakov loop is calculated and the order of thephase transition as well as the critical temperatures are obtained for the color group SU(2 and SU(3. In both cases, our predictions are in good agreement with lattice calculations.
International Nuclear Information System (INIS)
Lee, B.W.
1976-01-01
Some introductory remarks to Yang-Mills fields are given and the problem of the Coulomb gauge is considered. The perturbation expansion for quantized gauge theories is discussed and a survey of renormalization schemes is made. The role of Ward-Takahashi identities in gauge theories is discussed. The author then discusses the renormalization of pure gauge theories and theories with spontaneously broken symmetry. (B.R.H.)
Observation of a Coulomb flux tube
Greensite, Jeff; Chung, Kristian
2018-03-01
In Coulomb gauge there is a longitudinal color electric field associated with a static quark-antiquark pair. We have measured the spatial distribution of this field, and find that it falls off exponentially with transverse distance from a line joining the two quarks. In other words there is a Coulomb flux tube, with a width that is somewhat smaller than that of the minimal energy flux tube associated with the asymptotic string tension. A confinement criterion for gauge theories with matter fields is also proposed.
Coulomb energy, vortices, and confinement
International Nuclear Information System (INIS)
Greensite, Jeff; Olejnik, Stefan
2003-01-01
We estimate the Coulomb energy of static quarks from a Monte Carlo calculation of the correlator of timelike link variables in the Coulomb gauge. We find, in agreement with Cucchieri and Zwanziger, that this energy grows linearly with distance at large quark separations. The corresponding string tension, however, is several times greater than the accepted asymptotic string tension, indicating that a state containing only static sources, with no constituent gluons, is not the lowest energy flux tube state. The Coulomb energy is also measured on thermalized lattices with center vortices removed by the de Forcrand-D'Elia procedure. We find that when vortices are removed, the Coulomb string tension vanishes
Chern-Simons induced spin factors in noncovariant gauges
International Nuclear Information System (INIS)
Tanaka, I.
1993-01-01
We study Chern-Simons induced spin factors in noncovariant metric-independent gauges, such as the axial gauge and the Coulomb gauge. These spin factors are defined without loop splitting. We find that they are equal to integers and have particular geometrical meanings. In the axial gauge, this integer is the writhe number of a link diagram defined by the projection of a loop to the time direction. In the Coulomb gauge, it is suggested that this integer is also the writhe number of a link diagram, defined by the projection of a loop to a spatial plane
The Coulomb Branch of 3d N= 4 Theories
Bullimore, Mathew; Dimofte, Tudor; Gaiotto, Davide
2017-09-01
We propose a construction for the quantum-corrected Coulomb branch of a general 3d gauge theory with N=4 supersymmetry, in terms of local coordinates associated with an abelianized theory. In a fixed complex structure, the holomorphic functions on the Coulomb branch are given by expectation values of chiral monopole operators. We construct the chiral ring of such operators, using equivariant integration over BPS moduli spaces. We also quantize the chiral ring, which corresponds to placing the 3d theory in a 2d Omega background. Then, by unifying all complex structures in a twistor space, we encode the full hyperkähler metric on the Coulomb branch. We verify our proposals in a multitude of examples, including SQCD and linear quiver gauge theories, whose Coulomb branches have alternative descriptions as solutions to Bogomolnyi and/or Nahm equations.
Energy Technology Data Exchange (ETDEWEB)
Klose, W; Schinkel, A P [Univ. Kassel (Germany). Inst. fuer Thermische Energietechnik
1998-09-01
The contribution models the pyrolysis of corn in a rotary kiln reactor. The model comprises a solution of the two-dimensional energy and mass balances for the solid phase. The movement of the solid matter inside the reactor is described by model equations. The influence of various operating parameters on the pyrolysis process is discussed, i.e. temperature, rotational speed, length and angle of inclination of the tube. (orig.) [Deutsch] In diesem Beitrag wird die Pyrolyse von Mais im Drehrohrreaktor modelliert. Das Modell beinhaltet die Loesung der 2dimensionalen Energie- und Stoffbilanzen fuer die feste Phase. Die Gutbewegung im Drehrohr wird mit Hilfe von Modellansaetzen beschrieben. Es wird der Einfluss der Betriebsparameter Temperatur, Drehzahl, Laenge und Neigungswinkel des Rohres auf die Pyrolyse diskutiert. (orig.)
Tensor gauge condition and tensor field decomposition
Zhu, Ben-Chao; Chen, Xiang-Song
2015-10-01
We discuss various proposals of separating a tensor field into pure-gauge and gauge-invariant components. Such tensor field decomposition is intimately related to the effort of identifying the real gravitational degrees of freedom out of the metric tensor in Einstein’s general relativity. We show that as for a vector field, the tensor field decomposition has exact correspondence to and can be derived from the gauge-fixing approach. The complication for the tensor field, however, is that there are infinitely many complete gauge conditions in contrast to the uniqueness of Coulomb gauge for a vector field. The cause of such complication, as we reveal, is the emergence of a peculiar gauge-invariant pure-gauge construction for any gauge field of spin ≥ 2. We make an extensive exploration of the complete tensor gauge conditions and their corresponding tensor field decompositions, regarding mathematical structures, equations of motion for the fields and nonlinear properties. Apparently, no single choice is superior in all aspects, due to an awkward fact that no gauge-fixing can reduce a tensor field to be purely dynamical (i.e. transverse and traceless), as can the Coulomb gauge in a vector case.
Topological resolution of gauge theory singularities
Saracco, Fabio; Tomasiello, Alessandro; Torroba, Gonzalo
2013-08-01
Some gauge theories with Coulomb branches exhibit singularities in perturbation theory, which are usually resolved by nonperturbative physics. In string theory this corresponds to the resolution of timelike singularities near the core of orientifold planes by effects from F or M theory. We propose a new mechanism for resolving Coulomb branch singularities in three-dimensional gauge theories, based on Chern-Simons interactions. This is illustrated in a supersymmetric SU(2) Yang-Mills-Chern-Simons theory. We calculate the one-loop corrections to the Coulomb branch of this theory and find a result that interpolates smoothly between the high-energy metric (that would exhibit the singularity) and a regular singularity-free low-energy result. We suggest possible applications to singularity resolution in string theory and speculate a relationship to a similar phenomenon for the orientifold six-plane in massive IIA supergravity.
Topological resolution of gauge theory singularities
Energy Technology Data Exchange (ETDEWEB)
Saracco, Fabio; Tomasiello, Alessandro; Torroba, Gonzalo
2013-08-21
Some gauge theories with Coulomb branches exhibit singularities in perturbation theory, which are usually resolved by nonperturbative physics. In string theory this corresponds to the resolution of timelike singularities near the core of orientifold planes by effects from F or M theory. We propose a new mechanism for resolving Coulomb branch singularities in three-dimensional gauge theories, based on Chern-Simons interactions. This is illustrated in a supersymmetric S U ( 2 ) Yang-Mills-Chern-Simons theory. We calculate the one-loop corrections to the Coulomb branch of this theory and find a result that interpolates smoothly between the high-energy metric (that would exhibit the singularity) and a regular singularity-free low-energy result. We suggest possible applications to singularity resolution in string theory and speculate a relationship to a similar phenomenon for the orientifold six-plane in massive IIA supergravity.
Adler's theorem in finite massless QED and possible extensions to non-Abelian gauge theories. II
International Nuclear Information System (INIS)
Bernstein, J.
1975-01-01
The indefinite metric produced by the ghost fields in the Coulomb gauge in Yang-Mills theories is discussed. It is shown that the ghosts greatly complicate the job of proving, or disproving, an Adler theorem in this gauge. An old result of Schwinger for Coulomb gauge Yang-Mills theories is also found to be compromised by ghosts. (Auth.)
Energy Technology Data Exchange (ETDEWEB)
Doellen, U.C. von
1996-12-01
The work concerns the task of control described as dispatching of extensive energy supply and distribution networks. Due to the special contractual situation, there are special long-term targets in firms, which must be achieved in addition to the extensive operational tasks of control and monitoring of the networks. The concepts introduced in the work offer a framework for a target-orientated design of computer-aided menus for this superior process control in the energy industry. (orig./GL) [Deutsch] Die Arbeit betrachtet die als Dispatching bezeichnete Aufgabe der Fuehrung ausgedehnter Energieversorgungs- und verteilungsnetze. Aus den speziellen Vertragssituationen ergeben sich in den Unternehmen besondere, langfristige Zielvorgaben an die mit der Betriebsfuehrung beauftragen Operateure, die zusaetzlich zu den umfangreichen operativen Aufgaben der Fuehrung und Ueberwachung der Netze zu erreichen sind. Die in der Arbeit vorgestellten Konzepte bieten den Rahmen fuer einen zielgerichteten Entwurf rechnergestuetzter Hilfsmittel fuer diese uebergeordnete Prozessfuehrung in der Energiewirtschaft. Das erstellte Gesamtsystem wird abschliessend zur Loesung einer konkreten, energiewirtschaftlichen Problemstellung eingesetzt. Die entwickelte Anwendungsloesung wird als Hilfsmittel fuer die technische und vertragliche Optimierung im Dispatching eingesetzt. Wesentliche Zielsetzung ist ein technisch und wirtschaftlich optimaler Einsatz von Energiespeichern zur Deckung von Spitzenlasten. (orig./GL)
Energy Technology Data Exchange (ETDEWEB)
Wilderer, P.A. [ed.; Faulstich, M. [ed.; Rothemund, C. [ed.; Angerhoefer, R. [ed.
1996-10-01
Sewage sludge is a material requiring utilization and disposal. A profound change is due with the prohibition from the year 2005 to deposit untreated sewage sludge at landfills. As it will hardly be possible to use all sewage sludge in farming, thermal disposal will be indispensable. A major problem consists in forecasting the quantities of sewage sludge requiring processing and determining the corresponding plant capacities. If the problem is varied, so are the solutions offered. Therefore, a final panel discussion was held where representatives of science, the ministries and the interest groups concerned had the possibility to voice their opinions. (orig.) [Deutsch] Es gilt Klaerschlaemme zu verwerten und zu entsorgen. Hier ist eine nachhaltige Veraenderung vor allem deshalb zu erwarten, da ab dem Jahr 2005 die Ablagerung nicht vorbehandelter Klaerschlaemme untersagt ist. Da aber kaum saemtliche Klaerschlaemme landwirtschaftlich zu verwerten sind, ist das Standbein thermische Behandlung unverzichtbar. Ein grundsaetzliches Problem ist hier die Prognose der zukuenftig zu behandelnden Mengen und des sich daraus ergebenden Anlagenbedarfs. So vielfaeltig wie das Problem, so vielfaeltig sind die Auffassungen zur Loesung desselben. In einer abschliessenden Podiumsdiskussion hatten daher Vertreter der Wissenschaft, der Ministerien sowie der einschlaegigen Interessenverbaende die Moeglichkeit, ihre Positionen zu verdeutlichen. (orig.)
Adler's theorem in finite massless QED and possible extensions to non- Abelian gauge theories II
Bernstein, J
1975-01-01
For pt.I see ibid., vol.B95, p.461 (1975). The indefinite metric produced by the ghost fields in the Coulomb gauge in Yang-Mills theories is discussed. It is shown that the ghosts greatly complicate the job of proving, or disproving, an Adler theorem in this gauge. An old result of Schwinger (1962) for Coulomb gauge Yang-Mills theories is also found to be compromised by ghosts. (7 refs).
Three-Dimensional Gauge Theories and ADE Monopoles
Tong, David
1998-01-01
We study three-dimensional N=4 gauge theories with product gauge groups constructed from ADE Dynkin diagrams. One-loop corrections to the metric on the Coulomb branch are shown to coincide with the metric on the moduli space of well-seperated ADE monopoles. We propose that this correspondence is exact.
Pure Gauge theory in crystal lattice and Coulomb gases
International Nuclear Information System (INIS)
Marchetti, D.H.U.
1985-01-01
A method for the construction of classical gases, starting from a pure gauge theory, is described. The method is applied to the U(1) gauge theory in two spatial dimensions. For this model it's seen the vaccua appearing as a consequence of the quantization ambiguity. The connection between the vaccua and the confinement is discussed. (Author) [pt
CargoMover - the driverless 'truck on rails'; CargoMover - der fahrerlose 'Lkw auf Schienen'
Energy Technology Data Exchange (ETDEWEB)
Mairhofer, F. [Siemens AG, Erlangen (Germany). Transportation Systems, Cargo Logistics; Janssen, G. [DB Netz AG, NL West, Duisburg (Germany)
2003-07-01
Year after year, more and more freight is transported in Europe. Most of it is transported by road, because users currently see the truck as the fastest, most flexible and most economic solution. But road haulage is already leading to a lot of congestion, so that is it becoming more and more important to shift traffic onto the railways. The high-availability CargoMover {sup registered} system complements existing rail freight transport services. It combines the strategic advantages of truck and rail transport and offers flexible driverless rail freight transport to individual destinations - including at regional and local level, and for short-term requirements or small loads. (orig.) [German] Jahr fuer Jahr werden in Europa mehr Gueter bewegt. Der Grossteil dieser Transporte erfolgt auf der Strasse, weil der LKW von vielen Nutzern momentan als die schnellste, flexibelste und wirtschaftlichste Loesung angesehen wird. Schon heute fuehrt der Lkw-Verkehr aber zu vielen Staus, so dass es immer wichtiger wird, mehr Transportvolumen auf die Schiene zu bringen. Der CargoMover {sup registered} komplettiert als hochverfuegbares System das Gueterverkehrsangebot auf der Schiene. Er verbindet die strategischen Vorteile des Lkw mit denen des Bahnsystems und ermoeglicht fahrerlosen, zielreinen und flexiblen Gueterverkehr auf der Schiene - auch im Regional- und Nahverkehr, bei kurzfristigem Bedarf oder kleineren Losgroessen. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Klueppel, M.; Alshuth, T.; Schuster, R.H. [Deutsches Inst. fuer Kautschuktechnologie e.V., Hannover (Germany)
1998-12-31
ABS braking on dry and wet roads involves different mechanisms of rubber friction on rough surfaces. This improves car safety in terms of higher manoeuvrability and shorter braking lengths especially on wet roads. Current research focuses on optimisation of tyrecontact surface materials with better traction characteristics and lower rolling resistance. Laboratory predictions of the traction properties of tyre faces must be based on fundamental knowledge of the local sliding phenomena in the tyre contact surface and the resulting energy dissipation during ABS braking. This contribution therefore attempts to relate the elementary mechanisms of tyre mechanics in ABS braking processes to theoretical concepts of rubber friction on rough surfaces. [Deutsch] Beim ABS-Bremsen auf trockenen und nassen Strassen werden unterschiedliche Mechanismen der Gummireibung auf rauhen Oberflaechen wirksam. In der Summe bewirkt dies eine hoehere Fahrsicherheit, da neben der Manoevrierfaehigkeit des Autos auch der Bremsweg, vor allem auf nassen Strassen, verkuerzt sein kann. In diesem Zusammenhang wird zur Zeit verstaerkt an einer Optimierung von Laufflaechenmaterialien durch den Einsatz von massgeschneiderten Loesungs-SBR-Typen in Verbindung mit gefaellten Kieselsaeuren gearbeitet, wodurch neben einer Verbesserung der Traktionseigenschaften beim ABS-Bremsen auch eine Verringerung des Rollwiderstandes erreicht wird. Fuer Laborvorhersagen der Traktionseigenschaften von Reifenlaufflaechen ist ein grundlegendes Verstaendnis der lokalen Gleitphaenomene in der Reifenaufstandsflaeche und der damit verbundenen Energiedissipation beim ABS-Bremsen erforderlich. In dieser Arbeit wird deshalb angestrebt, die elementaren Mechanismen der Reifenmechanik beim ABS-Bremsen mit theoretischen Konzepten der Gummireibung auf rauhen Oberflaechen in Verbindung zu bringen. (orig.)
Coulomb correlations in many-electron systems on the level of self-consistent fields
International Nuclear Information System (INIS)
Warken, M.
1991-06-01
It was the aim of this thesis to show means and ways, in order to regard Coulomb correlation already on the SCF level. As mean to facilitate this general averaged fields should serve. For this first in chapter I was shown, how by means of suitable gauge fixings terms into effective potentials of the Hartree-Fock or g-Hartree type are introduced, which permit an interpretation as correlation density or as effective coupling constant. The following considerations were exemplarily performed on the cases g-Hartree (in Coulomb gauge) and on f-Hartree-Fock. (orig./HSI) [de
Instantons, three-dimensional gauge theory, and the Atiyah-Hitchin manifold
Dorey, N.; Khoze, V.V.; Mattis, M.P.; Tong, D.; Vandoren, S.
1997-01-01
We investigate quantum effects on the Coulomb branch of three-dimensional N = 4 supersymmetric gauge theory with gauge group SU(2). We calculate perturbative and one-instanton contributions to the Wilsonian effective action using standard weakcoupling methods. Unlike the four-dimensional case,
Hamiltonian formulation of QCD in the Schwinger gauge
International Nuclear Information System (INIS)
Schutte, D.
1989-01-01
The structure of the Hamiltonian related to a regularized non-Abelian gauge field theory is discussed in the light of different choices for gauge-invariant wave functionals (loop space, Coulomb, axial, Schwinger gauge). Arguments are given for the suggestion that the Schwinger gauge offers a specially suited framework for the computation of bound-state (hadron) properties. The most important reasons are the manifest rotation invariance, the lack of a Gribov horizon (giving standard many-body techniques a better chance), and the fact that a regularization analogous to the lattice regularization is easily implementable. Some details of the Schwinger-gauge Hamiltonian theory are discussed
Path integral quantization in the temporal gauge
International Nuclear Information System (INIS)
Scholz, B.; Steiner, F.
1983-06-01
The quantization of non-Abelian gauge theories in the temporal gauge is studied within Feynman's path integral approach. The standard asymptotic boundary conditions are only imposed on the transverse gauge fields. The fictituous longitudinal gauge quanta are eliminated asymptotically by modified boundary conditions. This abolishes the residual time-independent gauge transformations and leads to a unique fixing of the temporal gauge. The resulting path integral for the generating functional respects automatically Gauss's law. The correct gauge field propagator is derived. It does not suffer from gauge singularities at n x k = 0 present in the usual treatment of axial gauges. The standard principal value prescription does not work. As a check, the Wilson loop in temporal gauge is calculated with the new propagator. To second order (and to all orders in the Abelian case) the result agrees with the one obtained in the Feynman and Coulomb gauge. (orig.)
Deconfinement on ℝ2×SL1×Sβ1 for all gauge groups and duality to double Coulomb gas
International Nuclear Information System (INIS)
Teeple, Brett
2016-01-01
I study finite-temperature N=1 super Yang-Mills for any gauge group G=A N ,B N ,C N ,D N ,E 6,7,8 ,F 4 ,G 2 , compactified from four dimensions on a torus, ℝ 2 ×S L 1 ×S β 1 . I examine in particular the low temperature regime L≪β=1/T, where L is the length of the spatial circle with periodic boundary conditions and with anti-periodic boundary conditions for the adjoint gauginos along the thermal cycle S β 1 . For small such L we are in a regime were semiclassical calculations can be performed and a transition occurs at T c much smaller than 1/NL. The transition is mediated by the competition between non-perturbative objects including ‘exotic’ topological molecules: neutral and magnetic bions composed of BPS and KK monopole constituents, with r=rank(G) different charges in the co-root lattice of the gauge group G, and the perturbative electrically charged W-bosons (along with their wino superpartners). The difference from non-SUSY theories here is that the Higgsing along the thermal cycle gives rise to a light modulus scalar field which couples to both bion-instantons and the W-bosons, and mediates a transition near T c where the bions and W-bosons compete with equal strengths. The transition is seen to be similar to previous studies on ℝ 3 ×S L 1 http://dx.doi.org/10.1007/JHEP11(2013)142; http://dx.doi.org/10.1007/JHEP09(2014)040; http://dx.doi.org/10.1007/JHEP03(2013)087; http://dx.doi.org/10.1007/JHEP09(2013)128 with general gauge group where a first order transition was found for all groups, but a second order one for the case of SU(2) on the torus ℝ 2 ×S L 1 ×S β 1 , which was subjected to lattice studies in http://dx.doi.org/10.1007/JHEP11(2013)142. I determine a duality to a double Coulomb gas of neutral and magnetic bions of different charges of their constituent monopole-instantons, and W-bosons of both scalar and electric charges. Aharanov-Bohm interactions exist between magnetic bions and W-bosons, and scalar charges of W-bosons and
Energy Technology Data Exchange (ETDEWEB)
Flechner, B.A. [ABB Network Partner AG, Turgi (Switzerland). Abt. Business Management Systeme
1998-10-30
Competition on the electricity market puts high pressure on costs and creates an avalanche of innovation which energy providers and system suppliers have to cope with. Systems for wholesaling and retailing of electrical energy and reservation of electrical grids must fulfill high demands not only in terms of technical innovations but also commercially. ABB now offers solutions and systems, which give its users the decisive edge in the market. New products and solutions for known technical problems can create noticeable savings. This creates a number of new business tasks which must be coped with as well and whose solutions will directly influence the success or failure of every energy provider.(orig). [Deutsch] Der Wettbewerb im Strommarkt bringt einen hohen Kostendruck mit sich und fuehrt zu einem enormen Innovationsschub, den Energieversorger und Systemlieferanten gleichermassen zu leisten und zu bewaeltigen haben. Neben Innvationen bei der Technik werden vor allem im kommerziellen Bereich sehr hohe Anforderungen an Systeme zum Grosshandel und Weiterverkauf von elektrischer Energie sowie zur Reservierung der elektrischen Netze gestellt. ABB bietet schon heute Loesungen und Systeme, die im freien Strommarkt den entscheidenden Wettbewerbsvorteil bringen koennen. Neue Produkte und Loesungen fuer bekannte technische Probleme koennen zu deutlichen Einsparungen fuehren. Darueber hinaus entstehen eine Unzahl neuer Aufgaben im kommerziellen Bereich, die ebenfalls zu meistern sind und deren Loesung sich unmittelbar auf Erfolg oder Misserfolg jedes Energieversorgers auswirkt. (orig.)
Gauge equivalence of the electrodynamics of charged bosons
International Nuclear Information System (INIS)
Sohn, R.; Haller, K.
1977-01-01
The quantum electrodynamics of charged scalar and vector bosons is formulated in the Lorentz gauge, and the effect of the charged particle--photon interaction on the subsidiary condition is explicitly taken into account. The results are extensions of earlier work on spinor quantum electrodynamics, but the presence of seagull vertices and anomalous current commutators in the case of the charged bosons make the extensions nontrivial. An operator gauge transformation that encompasses equations of motion as well as the commutator algebra of the field operators is developed; it is used to transform the theory from the Lorentz gauge to the Coulomb gauge
A gauge invariant theory for time dependent heat current
International Nuclear Information System (INIS)
Chen, Jian; ShangGuan, Minhui; Wang, Jian
2015-01-01
In this work, we develop a general gauge-invariant theory for AC heat current through multi-probe systems. Using the non-equilibrium Green’s function, a general expression for time-dependent electrothermal admittance is obtained where we include the internal potential due to the Coulomb interaction explicitly. We show that the gauge-invariant condition is satisfied for heat current if the self-consistent Coulomb interaction is considered. It is known that the Onsager relation holds for dynamic charge conductance. We show in this work that the Onsager relation for electrothermal admittance is violated, except for a special case of a quantum dot system with a single energy level. We apply our theory to a nano capacitor where the Coulomb interaction plays an essential role. We find that, to the first order in frequency, the heat current is related to the electrochemical capacitance as well as the phase accumulated in the scattering event. (paper)
Electronic cooling via interlayer Coulomb coupling in multilayer epitaxial graphene
Mihnev, Momchil T.; Tolsma, John R.; Divin, Charles J.; Sun, Dong; Asgari, Reza; Polini, Marco; Berger, Claire; de Heer, Walt A.; MacDonald, Allan H.; Norris, Theodore B.
2015-01-01
In van der Waals bonded or rotationally disordered multilayer stacks of two-dimensional (2D) materials, the electronic states remain tightly confined within individual 2D layers. As a result, electron–phonon interactions occur primarily within layers and interlayer electrical conductivities are low. In addition, strong covalent in-plane intralayer bonding combined with weak van der Waals interlayer bonding results in weak phonon-mediated thermal coupling between the layers. We demonstrate here, however, that Coulomb interactions between electrons in different layers of multilayer epitaxial graphene provide an important mechanism for interlayer thermal transport, even though all electronic states are strongly confined within individual 2D layers. This effect is manifested in the relaxation dynamics of hot carriers in ultrafast time-resolved terahertz spectroscopy. We develop a theory of interlayer Coulomb coupling containing no free parameters that accounts for the experimentally observed trends in hot-carrier dynamics as temperature and the number of layers is varied. PMID:26399955
Energy Technology Data Exchange (ETDEWEB)
Huettenrauch, Jens; Zoellner, Sylvana; Mueller-Syring, Gert [DBI Gastechnologisches Institut gGmbH, Freiberg (Germany); and others
2015-07-01
One of the main challenges in the energy transition is to integrate the increasing based on volatile renewable energy generated power in market and network. Based on actual distribution networks in Emsland in the study presented below was investigated, what contribution an intelligent coupling of electricity and gas distribution networks by means of power to gas (PtG) systems can do to solve this challenge. The investigations have shown, among other things, that the network expansion costs in particular can be significantly reduced by the coupling when otherwise an oversizing would be done by discrete power grid expansion measures. [German] Eine der wesentlichen Herausforderung bei der Energiewende besteht darin, die zunehmend auf volatilen erneuerbaren Energien basierende Stromerzeugung in Markt und Netz zu integrieren. Anhand realer Verteilungsnetze im Emsland wurde in der im Folgenden vorgestellten Studie untersucht, welchen Beitrag eine intelligente Kopplung von Strom- und Gasverteilungsnetzen mittels Power-to-Gas (PtG)-Anlagen zur Loesung dieser Herausforderung leisten kann. Die Untersuchungen haben unter anderem gezeigt, dass durch die Kopplung die Netzausbaukosten insbesondere dann signifikant reduziert werden koennen, wenn andernfalls eine Ueberdimensionierung durch diskrete Stromnetzausbaumassnahmen erfolgen wuerde.
Energy Technology Data Exchange (ETDEWEB)
Bonus, H. [ed.
1998-12-31
Thirty years ago, Thomas D. Crocker and John H. Dales came up with the idea of tradable permits for making environmental protection both economically and ecologically efficient. Since then, a heated and controversial discussion has been going on. Tradable permits were considered as unrealistic, contra-competitive, incompatible with political structures, and even as an attempt to treat Mother Nature as a whore. As a result, Germany still operates by the command-and-control principle, and there are no significant examples of emission trading. The first part of this publication reviews the theoretical discussion and practical experiemce so far, while the second part discusses the requirements that must be met by tradable permit systmes in order to make them practicable. [Deutsch] Dreissig Jahre Diskussion ueber Zertifikate zeigen, dass der Weg zu einer marktwirtschaftlich ausgerichteten Umweltpolitik steinig ist. Die bahnbrechende Idee von Thomas D. Crocker und John H. Dales, mit Zertifikaten Umweltschutz sowohl oekonomisch effizient wie auch oekologisch treffsicher zu realisieren, wurde in der Vergangenheit immer wieder von Zweifeln an der Praktikabilitaet einer solchen Loesung ueberlagert. So wurde der Handel mit Zertifikaten als unrealisierbar angesehen, wettbewerbs- und strukturpolitische Einwaende wurden angefuehrt, und man empfand die Vergabe von Rechten zur Umweltnutzung sogar als Prostitution von Mutter Natur. Als Folge hat Deutschland bis heute kein signifikantes Umsetzungsbeispiel vorzuweisen; das Ordnungsrecht beherrscht nach wie vor die Szene. Der erste Teil des Bandes beleuchtet zunaechst den Stand der theoretischen Diskussion und die bisher gemachten Erfahrungen mit Zertifikaten. Der zweite Teil ist den Anforderungen gewidmet, denen Zertifikatesysteme gerecht werden muessen, um Eingang in die Praxis zu finden. (orig.)
Higgs phase in non-Abelian gauge theories
International Nuclear Information System (INIS)
Kaymakcalan, O.S.
1981-06-01
A non-Abelian gauge theory involving scalar fields with non-tachyonic mass terms in the Lagrangian is considered, in order to construct a finite energy density trial vacuum for this theory. The usual scalar potential arguments suggest that the vacuum of such a theory would be in the perturbative phase. However, the obvious choices for a vacuum in this phase, the Axial gauge and the Coulomb gauge bare vacua, do not have finite energy densities even with an ultraviolet cutoff. Indeed, it is a non-trivial problem to construct finite energy density vacua for non-Abelian gauge theories and this is intimately connected with the gauge fixing degeneracies of these theories. Since the gauge fixing is achieved in the Unitary gauge, this suggests that the Unitary gauge bare vacuum might be a finite energy trial vacuum and, despite the form of the scalar potential, the vacuum of this theory might be in a Higgs phase rather than the perturbative phase
Energy Technology Data Exchange (ETDEWEB)
Pankow, D. [ed.] [Halle-Wittenberg Univ., Halle (Germany). Inst. fuer Pharmakologie und Toxikologie; Verkoyen, C. [ed.] [Deutsche Forschungsanstalt fuer Luft- und Raumfahrt e.V. (DLR), Bonn (Germany). Projekttraegerschaften fuer Arbeit, Umwelt und Gesundheit; Wolna, P. [ed.] [Halle-Wittenberg Univ., Halle (Germany). Inst. fuer Pharmakologie und Toxikologie; Wuenscher, U. [ed.] [Halle-Wittenberg Univ., Halle (Germany). Inst. fuer Pharmakologie und Toxikologie
1993-12-31
The present volume is based on contributions to the workshop on ``Toxicological and industrial-medical aspects of exposure to dichloromethane and other aliphatic halocarbons`` which took place in Halle (Saale) on 25 November 1993. The purpose of the master project was to examine by animal experiment the effects of certain noxions factors on moderate CO hypoxia and the cardiovascular system as a whole following DCM intoxication, in particular the additional uptake of solvents and drings. Another part of the project consisted in specific examinations of gene toxicity. (orig./MG) [Deutsch] Der vorliegende Berichtsband entstand aus Beitraegen eines am 25. November 1993 in Halle (Saale) stattgefundenen Workshops ``Toxikologische und arbeitsmedizinische Aspekte der Exposition gegenueber Dichlormethan und anderen aliphatischen Halogenkohlenwasserstoffen``. Das Ziel des Vorhabens bestand darin, tierexperimentell die Beeinflussung der moderaten CO-Hypoxie nach DCM-Aufnahme durch verschiedene Faktoren, insbesondere durch zusaetzliche Aufnahme von Loesungs- und Arzneimitteln zu untersuchen sowie Wirkungen auf das Herz-Kreislauf-System zu erfassen. Weiterhin erfolgten gezielte Untersuchungen zur Gentoxizitaet. (orig./MG)
Van Hooydonk, G
2000-11-01
Following recent work in search for a universal function (Van Hooydonk, Eur. J. Inorg. Chem., (1999), 1617), we test four symmetric +/- a(n)Rn potentials for reproducing molecular potential energy curves (PECs). Classical gauge symmetry for 1/R-potentials results in generic left right asymmetric PECs. A pair of symmetric perturbed Coulomb potentials is quantitatively in accordance with observed PECs. For a bond, a four-particle system, charge inversion (a parity effect, atom chirality) is the key to explain this shape generically. A parity adapted Hamiltonian reduces from ten to two terms and to a soluble Bohr-like formula, a Kratzer (1 - Re/R)2 potential. The result is similar to the combined action of spin and wave function symmetry upon the Hamiltonian in Heitler-London theory. Analytical perturbed Coulomb functions varying with (1 - Re/R) scale attractive and repulsive branches of PECs for 13 bonds H2, HF, LiH, KH, AuH, Li2, LiF, KLi, NaCs, Rb2, RbCs, Cs2 and I2 in a single straight line. The 400 turning points for 13 bonds are reproduced with a deviation of 0.007 A at both branches. For 230 points at the repulsive side, the deviation is 0.003 A. The perturbed electrostatic Coulomb law is a universal molecular function. Ab initio zero molecular parameter functions give PECs of acceptable quality, just using atomic ionisation energies. The function can be used as a model potential for inverting levels and gives a first principle's comparison of short- and long-range interactions, important for the study of cold atoms. Wave-packet dynamics, femto-chemistry applied to the crossing of covalent and ionic curves, can provide evidence for this theory. We anticipate this scale/shape invariant scheme applies to smaller scales in nuclear and high-energy particle physics. For larger gravitational scales (Newton 1/R potentials), problems with super-unification are discussed. Reactions between hydrogen and antihydrogen, feasible in the near future, will probably produce
Energy Technology Data Exchange (ETDEWEB)
Kreitner, K.F. [Mainz Univ. (Germany). Klinik mit Poliklinik fuer Radiologie; Grebe, P. [Mainz Univ. (Germany). Klinik mit Poliklinik fuer Radiologie; Kersjes, W. [Mainz Univ. (Germany). Klinik mit Poliklinik fuer Radiologie; Runkel, M. [Mainz Univ. (Germany). Klinik fuer Unfallchirurgie; Kirschner, P. [Elisabeth-Hospital, Mainz (Germany). Abt. fuer Unfall- und Wiederherstellungschirurgie St. Vincenz; Schild, H.H. [Mainz Univ. (Germany). Klinik mit Poliklinik fuer Radiologie
1994-02-01
In a prospective study possible indications for MR arthrography of the shoulder were evaluated. 37 patients were examined before and after intraarticular administration of a 2-mmolar solution of Gd-DTPA. MR arthrography was performed if there was no joint effusion and/or an uncertain finding concerning the rotator cuff or the capsulolabral complex on plain MR images. MR arthrography leads to a better demonstration of labrum pathology in 11/22 patients and to a superior delineation of the capsuloligamentous apparatus in 20/22 cases. In 9/15 patients with impingement lesions MR arthrography allowed a differentiation of severe tendinitis from partial and small full-thickness tears of the rotator cuff. MR arthrography of the shoulder joint enhances the accuracy of MR in case of an uncertain finding on plain MR images. (orig.) [Deutsch] In einer prospektiven Studie sollten Einsatzmoeglichkeiten der MR-Arthrographie bei Erkrankungen des Schultergelenkes herausgearbeitet werden. 37 Patienten wurden sowohl nativ als auch nach intraartikulaerer Gabe einer 2mmolaren Gd-DTPA-Loesung untersucht. Voraussetzungen fuer die KM-Gabe waren ein fehlender Gelenkerguss und/oder ein unklarer Befund des Labrum-Kapsel-Komplexes oder der Rotatorenmanschette in der Nativuntersuchung. Durch die MR-Arthrographie wurde bei 11/22 Patienten eine verbesserte Darstellung der Labrumpathologie erzielt; in 20/22 Faellen ergabe sich eine zuverlaessige Beurteilung der Gelenkkapsel. Bei 9/15 Patienten mit Erkrankungen der Rotatorenmanschette konnten Tendinitiden von partiellen und kleinen kompletten Rotatorenmanschettenrupturen sicher differenziert werden. Die MR-Arthrographie des Schultergelenkes fuehrt bei nicht eindeutigen Befunden in der Nativuntersuchung zu einer verbesserten Treffsicherheit der MR-Diagnostik. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Kaulich, T.W.; Nuesslin, F. [Universitaetsklinik fuer Radioonkologie, Tuebingen (Germany). Abt. Medizinische Physik; Zurheide, J. [BrainLAB AG, Heimstetten (Germany); Fluehs, D. [Abt. Strahlentherapie, Bereich klinische Strahlenphysik, Universitaetsklinikum Essen (Germany); Haug, T. [Isotopenlabor der Univ. Tuebingen (Germany); Bamberg, M. [Abt. Radioonkologie, Universitaetsklinik fuer Radioonkologie, Tuebingen (Germany)
2001-11-01
, Oberflaechenkontaminationspruefung, Dichtheitspruefung, Dosisleistungsueberpruefung. Die Oberflaechenkontaminationspruefung besteht aus einer feuchten Wischprobe unter leichtem Druck. Zur Ueberpruefung der Dichtheit der {sup 106}Ru-Augenapplikatoren wurde ein klinisch relevantes Szenario entwickelt, bei dem der Kontakt der Augenapplikatoren mit Humangewebe simuliert wird. Dabei wird der Applikator mehrere Tage in Ringer-Loesung eingelegt. Die zertifizierten Energiedosisleistungsangaben des Herstellers werden mit einem 1 mm{sup 3} grossen Plastikszintillator auf Konsistenz geprueft. Ergebnisse: Bei den klinikinternen Eingangspruefungen von {sup 106}Ru-Augenapplikatoren unterschiedlicher Groesse ergaben sich folgende Resultate: Die Dichtheitspruefung wurde an sieben Applikatoren durchgefuehrt. Dabei wurden Kontaminationen bei den Wischproben bis 57 Bq und in der Ringer-Loesung bis 520 Bq gemessen. Bei der dosimetrischen Konsistenzpruefung der zertifizierten Dosisleistungsangabe von 14 Applikatoren zeigte sich bei sechs Applikatoren gute Uebereinstimmung mit einem Variationskoeffizienten von 2,6%. Bei acht Applikatoren lagen die Abweichungen zwischen -37% und +74%, d.h., die Spannweite dieser nicht akzeptablen Applikatoren betrug 111%. Die Ergebnisse wurden exemplarisch durch externe Begutachtung bestaetigt. Schlussfolgerung: Bei der klinikinternen Eingangspruefung von {sup 106}Ru-Augenapplikatoren wurden schwerwiegende therapierelevante Schwachstellen der industriellen Qualitaetssicherung festgestellt. Es ist deshalb notwendig, dass {sup 106}Ru-Augenapplikatoren vor klinischem Einsatz intern ueberprueft werden. Die hierzu entwickelte Eingangspruefung kann von anderen Kliniken direkt uebernommen werden. (orig.)
International Nuclear Information System (INIS)
Arodz, H.
1987-01-01
The two formulations of quantum theory of the free electromagnetic field are presented. In the Coulomb gauge approach the independent dynamical variables have been identified and then, in order to quantize the theory, it has been sufficient to apply the straightforward canonical quantization. In the Gupta-Bleuler approach the auxilliary theory is first considered. The straightforward canonical quantization of it leads to the quantum theory defined in the space G with indefinite norm. 15 refs. (author)
Energy Technology Data Exchange (ETDEWEB)
Wolter, C.; Rolin, P. [Weber-Ingenieure (Germany); Grothkopp, H. [Linde-KCA-Dresden GmbH (Germany)
1999-07-01
At the Radeberg sewage treatment plant of the local administration union (AZV) 'Obere Roeder', the first entirely joint co-fermentation facility for sewage sludge, organic waste and organic trade waste to have been erected in all Germany went operative. Expected turnover rates and gas yields of the fermentation plant could be attained subject to the concentrations of materials processed during the start-up phase. The advantages of co-fermentation at sewage treatment plant lie in the perfect matching of sewage treatment and sludge digestion on the one hand with organic waste fermentation on the other hand, so that the respective advantages complement each other while the disadvantages are balanced out by the combination. In terms of environmentally compatible, sustainable processing of organic waste and production residues, co-fermentation at sewage treatment plant represents a convenient and economical solution. (orig.) [German] Auf der Klaeranlage des AZV 'Obere Roeder' in Radeberg ist zum ersten Mal in Deutschland eine vollstaendig gemeinsame Covergaerung von Klaerschlamm, Bioabfaellen und gewerblichen organischen Reststoffen in Betrieb gegangen. Erwartete Umsatzleistungen und Gasausbeuten der Vergaerungsanlage konnten entsprechend der erzielten Stoffkonzentrationen in der Inbetriebnahmephase erreicht werden. Die Vorteile der Covergaerung auf Klaeranlagen liegen in der perfekten Abstimmung zwischen Klaeranlage und Klaerschlammfaulung einerseits und der Vergaerung von Bioabfaellen andererseits, so dass sich die Vorteile der jeweiligen Verfahren ergaenzen, bzw. sich die Nachteile durch die Kombination beider Verfahren aufheben. Im Hinblick auf oekologische, nachhaltige Verwertung organischer Abfaelle und Produktionsreststoffe bietet die Covergaerung auf Klaeranlagen eine sinnvolle, sich auch wirtschaftlich rechnende Loesung. (orig.)
Electron transport in the presence of a Coulomb field
International Nuclear Information System (INIS)
Burgdoerfer, J.; Gibbons, J.
1990-01-01
We analyze the modifications of the transport behavior of electrons in dense media due to the presence of a strong Coulomb field generated by an ion moving initially in close phase-space correlation with the electrons. These modifications play a profound role in convoy electron emission in ion-solid collisions. The transport behavior is studied within the framework of a classical phase-space master equation. The nonseparable master equation is solved numerically using test-particle discretization and Monte Carlo sampling. In the limit of vanishing Coulomb forces the master equation becomes separable and can be reduced to standard one-dimensional kinetic equations for free-electron transport that can be solved exactly. The comparison to free-electron transport is used to gauge both the reliability of test-particle discretization and the significance of Coulomb distortion of the distribution functions. Applications to convoy-electron emission are discussed
Itoh, Satoru G; Okumura, Hisashi
2013-03-30
We propose a new type of the Hamiltonian replica-exchange method (REM) for molecular dynamics (MD) and Monte Carlo simulations, which we refer to as the Coulomb REM (CREM). In this method, electrostatic charge parameters in the Coulomb interactions are exchanged among replicas while temperatures are exchanged in the usual REM. By varying the atom charges, the CREM overcomes free-energy barriers and realizes more efficient sampling in the conformational space than the REM. Furthermore, this method requires only a smaller number of replicas because only the atom charges of solute molecules are used as exchanged parameters. We performed Coulomb replica-exchange MD simulations of an alanine dipeptide in explicit water solvent and compared the results with those of the conventional canonical, replica exchange, and van der Waals REMs. Two force fields of AMBER parm99 and AMBER parm99SB were used. As a result, the CREM sampled all local-minimum free-energy states more frequently than the other methods for both force fields. Moreover, the Coulomb, van der Waals, and usual REMs were applied to a fragment of an amyloid-β peptide (Aβ) in explicit water solvent to compare the sampling efficiency of these methods for a larger system. The CREM sampled structures of the Aβ fragment more efficiently than the other methods. We obtained β-helix, α-helix, 3(10)-helix, β-hairpin, and β-sheet structures as stable structures and deduced pathways of conformational transitions among these structures from a free-energy landscape. Copyright © 2012 Wiley Periodicals, Inc.
Cirafici, M.; Sinkovics, A.; Szabo, R.J.
2009-01-01
We study the relation between Donaldson–Thomas theory of Calabi–Yau threefolds and a six-dimensional topological Yang–Mills theory. Our main example is the topological U(N) gauge theory on flat space in its Coulomb branch. To evaluate its partition function we use equivariant localization techniques
Infrared Fixed Point Physics in ${\\rm SO}(N_c)$ and ${\\rm Sp}(N_c)$ Gauge Theories
DEFF Research Database (Denmark)
Ryttov, Thomas A.; Shrock, Robert
2017-01-01
We study properties of asymptotically free vectorial gauge theories with gauge groups $G={\\rm SO}(N_c)$ and $G={\\rm Sp}(N_c)$ and $N_f$ fermions in a representation $R$ of $G$, at an infrared (IR) zero of the beta function, $\\alpha_{IR}$, in the non-Abelian Coulomb phase. The fundamental, adjoint......_{\\bar\\psi\\psi,IR}$ increases monotonically with decreasing $N_f$ in the non-Abelian Coulomb phase. Using this property, we give a new estimate of the lower end of this phase for some specific realizations of these theories....
Five-dimensional gauge theory and compactification on a torus
Haghighat, B.; Vandoren, S.J.G.
2011-01-01
We study five-dimensional minimally supersymmetric gauge theory compactified on a torus down to three dimensions, and its embedding into string/M-theory using geometric engineering. The moduli space on the Coulomb branch is hyperkaehler equipped with a metric with modular transformation properties.
Quantum electrodynamics in the light-front Weyl gauge
International Nuclear Information System (INIS)
Przeszowski, J.; Naus, H.W.; Kalloniatis, A.C.
1996-01-01
We examine (3+1)-dimensional QED quantized in the open-quote open-quote front form close-quote close-quote with finite open-quote open-quote volume close-quote close-quote regularization, namely, in discretized light-cone quantization. Instead of the light-cone or Coulomb gauges, we impose the light-front Weyl gauge A - =0. The Dirac method is used to arrive at the quantum commutation relations for the independent variables. We apply open-quote open-quote quantum-mechanical gauge fixing close-quote close-quote to implement Gauss close-quote law, and derive the physical Hamiltonian in terms of unconstrained variables. As in the instant form, this Hamiltonian is invariant under global residual gauge transformations, namely, displacements. On the light cone the symmetry manifests itself quite differently. copyright 1996 The American Physical Society
Gauge bridges in classical field theory; Eichbruecken in der klassischen Feldtheorie
Energy Technology Data Exchange (ETDEWEB)
Jakobs, S.
2009-03-15
In this thesis Poisson structures of two classical gauge field theories (Maxwell-Klein-Gordon- and Maxwell-Dirac-system) are constructed using the parametrix construction of Green's functions. Parametrices for the Maxwell-Klein-Gordon- and Maxwell-Dirac-system are constructed in Minkowski space and this construction is later generalized to curved space times for the Maxwell-Klein-Gordon-system. With these Green's functions Poisson brackets will be defined as Peierls brackets. Finally non-local, gauge invariant observables, the so-called 'gauge bridges'are constructed. Gauge bridges are the matrix elements of holonomy operators. It is shown, that these emerge from Poisson brackets of local, gauge invariant observables. (orig.)
Instanton Effects in Three-Dimensional Supersymmetric Gauge Theories with Matter
Dorey, N.; Tong, D.; Vandoren, S.
1998-01-01
Using standard field theory techniques we compute perturbative and instanton contributions to the Coulomb branch of three-dimensional supersymmetric QCD with N = 2 and N = 4 supersymmetry and gauge group SU(2). For the N = 4 theory with one massless flavor, we confirm the proposal of Seiberg and Witten that the Coulomb branch is the double-cover of the centered moduli space of two BPS monopoles constructed by Atiyah and Hitchin. Introducing a hypermultiplet mass term, we show that the asympto...
The electromagnetic potentials without the gauge transformations
Energy Technology Data Exchange (ETDEWEB)
Espinoza, Augusto; Chubykalo, Andrey; Rodriguez, Alejandro Gutierrez; Hernandez, Maria de los Angeles [Universidad Autonoma de Zacatecas (Mexico). Unidad Academica de Fisica
2011-07-01
In this note we show that the use of the Helmholtz theorem lead to derivation of uniquely determined electromagnetic potentials without making use of the gauge transformation. These potentials correspond to the potentials obtained by imposing so-called Coulomb condition (gauge) in the traditional approach. We show that the electromagnetic field comprises two components, one of which is characterized by its instantaneous action at a distance, whereas another one propagates in the retarded form with the velocity of light. One of the theoretical consequences of this new definition is that the electromagnetic potentials are real physical quantities as well as the electric and magnetic fields. We show that the reality of the electromagnetic potentials in quantum-mechanics is also a property of these potentials in the classical electrodynamics. Equations for potentials obtained in our approach are already separated with respect to vector and scalar potentials, so there is no necessity in using the gauge transformations and, accordingly, in making use of either Lorentz or Coulomb condition. The vector potential and scalar potential introduced thus are uniquely defined. The scalar potential is a generator of the so called instantaneous action at a distance, whereas the solenoidal vector potential can propagate with the velocity of light and it is responsible for the retarded action of the electromagnetic field. (author)
Energy Technology Data Exchange (ETDEWEB)
Ginter, F.
1997-12-31
The unsteady flow in a hydraulic machinery, affected by the interaction between guide vane and impeller, is simulated by a Finite-Element program. Based on the standard-k-{epsilon}-model modifications are investigated to model the turbulent flow. The low-Re-model of Lam-Brenhorst and a two-layer model is implemented for the calculation of the boundary layer. An algebraic Reynolds stress model is investigated for the simulation of the anisotropy of the turbulence structure. The turbulence models are compared by flows with characteristic properties. The pressure field of the incompressible flow is calculated by the mixed formulation and by solving the Poisson equation. The mixed formulation shows oscillations for the pressure field using elements with bilinear shape functions for the velocity and constant shape functions for the pressure, which are eliminated with a smoothing algorithm. An algorithm is implemented for the calculation of the unsteady interaction between fixed and moved blade rows, based on the method of overlapping regions, and is applied to the two-dimensional flow in an axial expansion turbine. (orig.) [Deutsch] Die instationaere Stroemung in einer hydraulischen Stroemungsmaschine, beruhend auf den Wechselwirkungen zwischen Leitrad und Laufrad, wird mit einem Finite-Elemente-Programm berechnet. Ausgehend vom Standard-k-{epsilon}-Modell werden Erweiterungen zur Modellierung der turbulenten Stroemung untersucht. Fuer die Berechnung der Grenzschicht werden das Low-Re-Modell nach Lam-Brenhorst und ein Zweischichtenmodell implementiert. Zur Erfassung der Anisotropie der Turbulenzstruktur wird ein algebraisches Reynoldsspannungsmodell untersucht. Die Turbulenzmodelle werden anhand von Stroemungen mit charakterischen Eigenschaften verglichen. Die Druckberechnung der inkompressiblen Stroemung erfolgt auf der Bais der gemischten Formulierung bzw. durch Loesung der Poissongleichung. Fuer die gemischte Formulierung zeigt das Druckfeld Oszillationen fuer
Energy Technology Data Exchange (ETDEWEB)
Brandt, B. [ZAE Bayern, Garching (Germany)
2004-07-01
Beanspruchung der Werkstoffe. Aufgabe des vorliegenden Beitrages war deshalb die Betrachtung handelsueblicher Werkstoffe und Inhibitoren auf ihre Eignung fuer Triple-Effekt-Absorptionskaeltemaschinen. Die Messungen wurden unter analogen Bedingungen in ruhender Loesung unter nahezu vollstaendigem Ausschluss von Luft durchgefuehrt. Die Untersuchungen haben ergeben, dass nichtrostender Stahl hinsichtlich seiner Materialstabilitaet besonders aussichtsreich ist. Weiterhin hat sich gezeigt, dass die Art des Inhibitors und das Zusammenwirken unterschiedlicher Phasen die Korrosion erheblich beeinflussen koennen. (Abstract Copyright [2004], Wiley Periodicals, Inc.)
Gauge invariance and the quark-antiquark static potential
International Nuclear Information System (INIS)
Cahill, K.; Stump, D.R.
1979-01-01
We calculate the quark-antiquark static potential to order g 4 in temporal-gauge quantum chromodynamics by constructing a suitably general family of gauge-invariant qq-bar states and then selecting the one whose energy is minimal for a given qq-bar separation r. Our results agree with those of conventional perturbation theory. We study various ways in which quark confinement might arise from nonperturbative effects related to the Gribov ambiguity. We find that the presence of long-range gauge fields can change the asymptotic behavior of the Coulomb Green's function from r -1 to r/sup -1/2/. We illustrate this possibility by a simple example. After making some simplifying assumptions, we obtain a minimally confining potential V (r) that rises logarithmically for large r
International Nuclear Information System (INIS)
Zet, G.
2002-01-01
The self-duality equations are important in gauge theories because they show the connection between gauge models with internal symmetry groups and gauge theory of gravity. They are differential equations of the first order and it is easier to investigate the solutions for different particular configurations of the gauge fields and of space-times.One of the most important property of the self-duality equations is that they imply the Yang-Mills field equations. In this paper we will prove this property for the general case of a gauge theory with compact Lie group of symmetry over a 4-dimensional space-time manifold. It is important to remark that there are 3m independent self-duality equations (of the first order) while the number of Yang-Mills equations is equal to 4m, where m is the dimension of the gauge group. Both of them have 4m unknown functions which are the gauge potentials A μ a (x), a = 1, 2, ....,m; μ = 0, 1, 2, 3. But, we have, in addition, m gauge conditions for A μ a (x), (for example Coulomb, Lorentz or axial gauge) which together with the selfduality equation constitute a system of 4m equations. The Bianchi identities for the self-dual stress tensor F μν a coincide with the Yang-Mills equations and do not imply therefore supplementary conditions. We use the axial gauge in order to obtain the self duality equations for a SU(2) gauge theory over a curved space-time. The compatibility between self-duality and Yang-Mills equations is studied and some classes of solutions are obtained. In fact, we will write the Einstein-Yang-Mills equations and we will analyse only the Yang-Mills sector. The Einstein equations can not be obtained of course from self-duality. They should be obtained if we would consider a gauge theory having P x SU(2) as symmetry group, where P is the Poincare group. More generally, a gauge theory of N-extended supersymmetry can be developed by imposing the self-duality condition. (author)
Yepez-Martinez, Tochtli; Civitarese, Osvaldo; Hess, Peter O.
2018-02-01
Starting from an algebraic model based on the QCD-Hamiltonian and previously applied to study meson states, we have developed an extension of it in order to explore the structure of baryon states. In developing our approach we have adapted concepts taken from group theory and non-perturbative many-body methods to describe states built from effective quarks and anti-quarks degrees of freedom. As a Hamiltonian we have used the QCD Hamiltonian written in the Coulomb Gauge, and expressed it in terms of effective quark-antiquark, di-quarks and di-antiquark excitations. To gain some insights about the relevant interactions of quarks in hadronic states, the Hamiltonian was approximately diagonalized by mapping quark-antiquark pairs and di-quarks (di-antiquarks) onto phonon states. In dealing with the structure of the vacuum of the theory, color-scalar and color-vector states are introduced to account for ground-state correlations. While the use of a purely color-scalar ground state is an obvious choice, so that colorless hadrons contain at least three quarks, the presence of coupled color-vector pairs in the ground state allows for colorless excitations resulting from the action of color objects upon it.
An N=2 gauge theory and its supergravity dual
Brandhuber, A
2000-01-01
We study flows on the scalar manifold of N=8 gauged supergravity in five dimensions which are dual to certain mass deformations of N=4 super Yang-Mill theory. In particular, we consider a perturbation of the gauge theory by a mass term for the adjoint hyper-multiplet, giving rise to an N=2 theory. The exact solution of the 5-dim gauged supergravity equations of motion is found and the metric is uplifted to a ten-dimensional background of type-IIB supergravity. Using these geometric data and the AdS/CFT correspondence we analyze the spectra of certain operators as well as Wilson loops on the dual gauge theory side. The physical flows are parametrized by a single non-positive constant and describe part of the Coulomb branch of the N=2 theory at strong coupling.
Super-Coulombic atom-atom interactions in hyperbolic media
Cortes, Cristian L.; Jacob, Zubin
2017-01-01
Dipole-dipole interactions, which govern phenomena such as cooperative Lamb shifts, superradiant decay rates, Van der Waals forces and resonance energy transfer rates, are conventionally limited to the Coulombic near-field. Here we reveal a class of real-photon and virtual-photon long-range quantum electrodynamic interactions that have a singularity in media with hyperbolic dispersion. The singularity in the dipole-dipole coupling, referred to as a super-Coulombic interaction, is a result of an effective interaction distance that goes to zero in the ideal limit irrespective of the physical distance. We investigate the entire landscape of atom-atom interactions in hyperbolic media confirming the giant long-range enhancement. We also propose multiple experimental platforms to verify our predicted effect with phonon-polaritonic hexagonal boron nitride, plasmonic super-lattices and hyperbolic meta-surfaces as well. Our work paves the way for the control of cold atoms above hyperbolic meta-surfaces and the study of many-body physics with hyperbolic media.
Instanton effects in three-dimensional supersymmetric gauge theories with matter
Dorey, N.; Tong, D.; Vandoren, S.
1998-01-01
Using standard field theory techniques we compute perturbative and instanton contributions to the Coulomb branch of three-dimensional supersymmetric QCD with N = 2 and N = 4 supersymmetry and gauge group SU(2). For the N = 4 theory with one massless flavor, we confirm the proposal of Seiberg and
One-instanton calculations in N=2 supersymmetric gauge theories
International Nuclear Information System (INIS)
Ito, Katsushi
1998-01-01
We study the low-energy effective action of N=2 supersymmetric gauge theories in the Coulomb branch. Using microscopic instanton calculus, we compute the one-instanton contribution to the pre potential for N=2 supersymmetric SU(N c ) Yang-Mills theory. We show that the microscopic result agrees with the exact solution. (Author). 23 refs
Matter fields near quantum critical point in (2+1)-dimensional U(1) gauge theory
International Nuclear Information System (INIS)
Liu Guozhu; Li Wei; Cheng Geng
2010-01-01
We study chiral phase transition and confinement of matter fields in (2+1)-dimensional U(1) gauge theory of massless Dirac fermions and scalar bosons. The vanishing scalar boson mass, r=0, defines a quantum critical point between the Higgs phase and the Coulomb phase. We consider only the critical point r=0 and the Coulomb phase with r>0. The Dirac fermion acquires a dynamical mass when its flavor is less than certain critical value N f c , which depends quantitatively on the flavor N b and the scalar boson mass r. When N f f c , the matter fields carrying internal gauge charge are all confined if r≠0 but are deconfined at the quantum critical point r=0. The system has distinct low-energy elementary excitations at the critical point r=0 and in the Coulomb phase with r≠0. We calculate the specific heat and susceptibility of the system at r=0 and r≠0, which can help to detect the quantum critical point and to judge whether dynamical fermion mass generation takes place.
Electromagnetic potentials without gauge transformations
International Nuclear Information System (INIS)
Chubykalo, A; Espinoza, A; Alvarado Flores, R
2011-01-01
In this paper, we show that the use of the Helmholtz theorem enables the derivation of uniquely determined electromagnetic potentials without the necessity of using gauge transformation. We show that the electromagnetic field comprises two components, one of which is characterized by instantaneous action at a distance, whereas the other propagates in retarded form with the velocity of light. In our attempt to show the superiority of the new proposed method to the standard one, we argue that the action-at-a-distance components cannot be considered as a drawback of our method, because the recommended procedure for eliminating the action at a distance in the Coulomb gauge leads to theoretical subtleties that allow us to say that the needed gauge transformation is not guaranteed. One of the theoretical consequences of this new definition is that, in addition to the electric E and magnetic B fields, the electromagnetic potentials are real physical quantities. We show that this property of the electromagnetic potentials in quantum mechanics is also a property of the electromagnetic potentials in classical electrodynamics.
On running couplings in gauge theories from type-IIB supergravity
Kehagias, A A
1999-01-01
We construct an explicit solution of type-IIB supergravity describing the strong coupling regime of a non-supersymmetric gauge theory. The latter has a running coupling with an ultraviolet stable fixed point corresponding to the N=4 SU(N) super-Yang-Mills theory at large N. The running coupling has a power law behaviour, argued to be universal, that is consistent with holography. Around the critical point, our solution defines an asymptotic expansion for the gauge coupling beta-function. We also calculate the first correction to the Coulombic quark-antiquark potential.
4d N=2 theories with disconnected gauge groups
Energy Technology Data Exchange (ETDEWEB)
Argyres, Philip C.; Martone, Mario [Physics Department, University of Cincinnati,PO Box 210011, Cincinnati OH 45221 (United States)
2017-03-28
In this paper we present a beautifully consistent web of evidence for the existence of interacting 4d rank-1 N=2 SCFTs obtained from gauging discrete subgroups of global symmetries of other existing 4d rank-1 N=2 SCFTs. The global symmetries that can be gauged involve a non-trivial combination of discrete subgroups of the U(1){sub R}, low-energy EM duality group SL(2,ℤ), and the outer automorphism group of the flavor symmetry algebra, Out(F). The theories that we construct are remarkable in many ways: (i) two of them have exceptional F{sub 4} and G{sub 2} flavor groups; (ii) they substantially complete the picture of the landscape of rank-1 N=2 SCFTs as they realize all but one of the remaining consistent rank-1 Seiberg-Witten geometries that we previously constructed but were not associated to known SCFTs; and (iii) some of them have enlarged N=3 SUSY, and have not been previously constructed. They are also examples of SCFTs which violate the Shapere-Tachikawa relation between the conformal central charges and the scaling dimension of the Coulomb branch vev. We propose a modification of the formulas computing these central charges from the topologically twisted Coulomb branch partition function which correctly compute them for discretely gauged theories.
Hadron masses in a gauge theory
International Nuclear Information System (INIS)
De Rujula, A.; Georgi, H.; Glashow, S.L.
1975-01-01
We explore the implications for hadron spectroscopy of the ''standard'' gauge model of weak, electromagnetic, and strong interactions. The model involves four types of fractionally charged quarks, each in three colors, coupling to massless gauge gluons. The quarks are confined within colorless hadrons by a long-range spin-independent force realizing infrared slavery. We use the asymptotic freedom of the model to argue that for the calculation of hadron masses, the short-range quark-quark interaction may be taken to be Coulomb-like. We rederive many successful quark-model mass relations for the low-lying hadrons. Because a specific interaction and symmetry-breaking mechanism are forced on us by the underlying renormalizable gauge field theory, we also obtain new mass relations. They are well satisfied. We develop a qualitative understanding of many features of the hadron mass spectrum, such as the origin and sign of the Σ-Λ mass splitting. Interpreting the newly discovered narrow boson resonances as states of charmonium, we use the model to predict the masses of charmed mesons and baryons
D3-brane shells to black branes on the Coulomb branch
International Nuclear Information System (INIS)
Giddings, Steven B.; Ross, Simon F.
2000-01-01
We use the AdS-CFT duality to study the special point on the Coulomb branch of N=4 SU(N) gauge theory which corresponds to a spherically symmetric shell of D3-branes. This point is of interest both because the spacetime region inside the shell is flat, and because this configuration gives a very simple example of the transition between D-branes in the perturbative string regime and the nonperturbative regime of black holes. We discuss how this geometry is described in the dual gauge theory, through its effect on the two-point functions and Wilson loops. In the calculation of the two-point function, we stress the importance of absorption by the branes. (c) 1999 The American Physical Society
Universal monopole scaling near transitions from the Coulomb phase.
Powell, Stephen
2012-08-10
Certain frustrated systems, including spin ice and dimer models, exhibit a Coulomb phase at low temperatures, with power-law correlations and fractionalized monopole excitations. Transitions out of this phase, at which the effective gauge theory becomes confining, provide examples of unconventional criticality. This Letter studies the behavior at nonzero monopole density near such transitions, using scaling theory to arrive at universal expressions for the crossover phenomena. For a particular transition in spin ice, quantitative predictions are made by mapping to the XY model and confirmed using Monte Carlo simulations.
The arithmetic of elliptic fibrations in gauge theories on a circle
Energy Technology Data Exchange (ETDEWEB)
Grimm, Thomas W. [Max-Planck-Institut für Physik,Föhringer Ring 6, 80805 Munich (Germany); Institute for Theoretical Physics,Utrecht University, Leuvenlaan 4, 3584 CE Utrecht (Netherlands); Center for Extreme Matter and Emergent Phenomena,Utrecht University, Leuvenlaan 4, 3584 CE Utrecht (Netherlands); Kapfer, Andreas [Max-Planck-Institut für Physik,Föhringer Ring 6, 80805 Munich (Germany); Klevers, Denis [Theory Group, Physics Department, CERN,CH-1211, Geneva 23 (Switzerland)
2016-06-20
The geometry of elliptic fibrations translates to the physics of gauge theories in F-theory. We systematically develop the dictionary between arithmetic structures on elliptic curves as well as desingularized elliptic fibrations and symmetries of gauge theories on a circle. We show that the Mordell-Weil group law matches integral large gauge transformations around the circle in Abelian gauge theories and explain the significance of Mordell-Weil torsion in this context. We also use Higgs transitions and circle large gauge transformations to introduce a group law for genus-one fibrations with multi-sections. Finally, we introduce a novel arithmetic structure on elliptic fibrations with non-Abelian gauge groups in F-theory. It is defined on the set of exceptional divisors resolving the singularities and divisor classes of sections of the fibration. This group structure can be matched with certain integral non-Abelian large gauge transformations around the circle when studying the theory on the lower-dimensional Coulomb branch. Its existence is required by consistency with Higgs transitions from the non-Abelian theory to its Abelian phases in which it becomes the Mordell-Weil group. This hints towards the existence of a new underlying geometric symmetry.
The arithmetic of elliptic fibrations in gauge theories on a circle
Grimm, Thomas W.; Kapfer, Andreas; Klevers, Denis
2016-06-01
The geometry of elliptic fibrations translates to the physics of gauge theories in F-theory. We systematically develop the dictionary between arithmetic structures on elliptic curves as well as desingularized elliptic fibrations and symmetries of gauge theories on a circle. We show that the Mordell-Weil group law matches integral large gauge transformations around the circle in Abelian gauge theories and explain the significance of Mordell-Weil torsion in this context. We also use Higgs transitions and circle large gauge transformations to introduce a group law for genus-one fibrations with multi-sections. Finally, we introduce a novel arithmetic structure on elliptic fibrations with non-Abelian gauge groups in F-theory. It is defined on the set of exceptional divisors resolving the singularities and divisor classes of sections of the fibration. This group structure can be matched with certain integral non-Abelian large gauge transformations around the circle when studying the theory on the lower-dimensional Coulomb branch. Its existence is required by consistency with Higgs transitions from the non-Abelian theory to its Abelian phases in which it becomes the Mordell-Weil group. This hints towards the existence of a new underlying geometric symmetry.
The arithmetic of elliptic fibrations in gauge theories on a circle
International Nuclear Information System (INIS)
Grimm, Thomas W.; Kapfer, Andreas; Klevers, Denis
2016-01-01
The geometry of elliptic fibrations translates to the physics of gauge theories in F-theory. We systematically develop the dictionary between arithmetic structures on elliptic curves as well as desingularized elliptic fibrations and symmetries of gauge theories on a circle. We show that the Mordell-Weil group law matches integral large gauge transformations around the circle in Abelian gauge theories and explain the significance of Mordell-Weil torsion in this context. We also use Higgs transitions and circle large gauge transformations to introduce a group law for genus-one fibrations with multi-sections. Finally, we introduce a novel arithmetic structure on elliptic fibrations with non-Abelian gauge groups in F-theory. It is defined on the set of exceptional divisors resolving the singularities and divisor classes of sections of the fibration. This group structure can be matched with certain integral non-Abelian large gauge transformations around the circle when studying the theory on the lower-dimensional Coulomb branch. Its existence is required by consistency with Higgs transitions from the non-Abelian theory to its Abelian phases in which it becomes the Mordell-Weil group. This hints towards the existence of a new underlying geometric symmetry.
Energy Technology Data Exchange (ETDEWEB)
Hadeler, A.
1999-08-01
The dispersal of trace substance in groundwater may be limited by dissolution and precipitation and, of particular interest in this paper, by sorption and desorption processes. These surface-active processes, which have a decisive influence on groundwater quality, depend on the concomitant geochemical conditions prevailing in the water, the constituents of the aquifer and on the surface properties of the solids. Taking the geochemical conditions prevailing naturally in brown coal mining areas as a point of departure this study was aimed at examining the influence of acidification processes on the transport behaviour inorganic pollutants for the example of zinc. For this purpose oxic column trials were carried out on sandy aquifer material. The data were supplemented by a detailed characterisation of the solid surfaces and modelled on the basis of a transport-reaction model as well as mechanistically with due regard to surface complexing. [German] Die Ausbreitung von Spurenstoffen im Grundwasser wird ausser durch Loesungs- und Faellungsprozesse vor allem durch Sorptions- bzw. Desorptionsvorgaenge limitiert. Diese fuer die Grundwasserqualitaet entscheidenden oberflaechenaktiven Prozesse sind von den variablen geochemischen Randbedingungen im Wasser, vom Stoffbestand des Aquifers und von den Oberflaecheneigenschaften der Feststoffe abhaengig. In Anlehnung an die natuerlichen im Bereich von Braunkohle-Abbaugebieten herrschenden geochemischen Bedingungen wurde der Einfluss von Versauerungsprozessen auf das Transportverhalten von anorganischen Schadstoffen, am Beispiel von Zink, auf der Basis von oxischen Saeulenversuchen an sandigem Aquifermaterial untersucht. Die Daten wurden durch eine detaillierte Charakterisierung der Feststoff-Oberflaechen ergaenzt und sowohl mit Hilfe eines Transport-Reaktionsmodells als auch mechanistisch unter Einbeziehung der Oberflaechenkomplexierung modelliert. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Grassl, H; Raschke, E
1995-11-01
At the beginning of the project there was considerable uncertainty as to the influence of clouds of all kinds on the energy budget of the atmosphere, the quantities and impact of aerosols, and, especially, the physics of high curl clouds. There was neither a possibility to model such cloud systems, nor did reliable measuring methods exist. This interconnected project contributed to the solution of these problems with the aim to create a solid basis of work for future climate researches. Simultaneously, measurements were carried out, satellite data analysed, aerosol data by different authors compiled and evaluated, and numerical simulations of cloud sheets carried out. (orig.) [Deutsch] Zu Beginn des Vorhabens herrschten erhebliche Unsicherheiten ueber den Einfluss von Wolken aller Arten auf den Energiehaushalt der Atmosphaere, ueber die Mengen und Wirkungen des Aerosols - und insbesondere ueber die Physik der hohen Cirren. Es gab keine Modelliermoeglichkeiten fuer solche Wolkensysteme - noch existierten zuverlaessige Messmoeglichkeiten. Das Verbundvorhaben sollte zur Loesung dieser Probleme beitragen mit dem Ziel, eine solide Arbeitsbasis fuer zukuenftige Aufgaben der Klimaforschung zu schaffen. Es wurden gleichzeitig Messungen durchgefuehrt, Satellitendaten analysiert, Aerosoldaten unterschiedlicher Autoren zusammengetragen und geprueft sowie numerische Simulationen von Wolkenfeldern durchgefuehrt. (orig.)
International Nuclear Information System (INIS)
McGowan, F.K.; Stelson, P.H.
1974-01-01
The theory of Coulomb excitation and a brief review of pertinent treatments of the Coulomb excitation process that are useful for the analysis of experiments are given. Examples demonstrating the scope of nuclear structure information obtainable from gamma spectroscopy are presented. Direct Elambda excitation of 232 Th is discussed in terms of the one phonon octupole vibrational spectrum. B(MI) reduced transition probabilities resulting from Coulomb excitation of odd-A deformed nuclei with heavy ions are presented as a test of the rotational model. The use of gamma ray coincidence and particle-gamma coincidence as tools for investigating Coulomb excitation is discussed. (U.S.)
Energy Technology Data Exchange (ETDEWEB)
Schmidberger, H.; Rave-Fraenk, M.; Kim, S.; Hille, A.; Pradier, O.; Hess, C.F. [Klinik fuer Strahlentherapie und Radioonkologie, Univ. Goettingen (Germany)
2003-10-01
Granulozyten in der Mundspuelfluessigkeit im Verlauf einer Radiotherapie oder einer Radio-chemotherapie (5-FU, Mitomycin) untersucht. Als Referenz wurden an vier freiwilligen, gesunden Probanden gleichartige Untersuchungen vorgenommen. Die Patienten/Probanden spuelten den Rachenraum 30 s mit 15 ml steriler physiologischer NaCl-Loesung. Das Sputum wurde zentrifugiert, mit 2 {mu}g/ml Akridin-Orange in 1 ml RPMI resuspendiert und anschliessend 15 min bei 37 C inkubiert. Die Zahl der neutrophilen Granulozyten in der Suspension wurde in einer Zaehlkammer unter dem Fluoreszenzmikroskop ausgewertet. Ergebnisse: Bei den Patienten wurden starke intra- und interindividuelle Schwankungen der enoralen neutrophilen Granulozytenanzahl in der Mundspuelfluessigkeit beobachtet. Tendenziell liess sich ein Zusammenhang zwischen dem Ausmass der radiogenen Mukositis und der Anzahl der neutrophilen Granulozyten in der Mundspuelfluessigkeit feststellen. Mit zunehmender Mukositis nahm die Anzahl der neutrophilen Granulozyten zu. Die Zunahme wurde durch eine Chemotherapie eher verstaerkt, die Behandlungspausen am Wochenende zeigten keinen Einfluss auf die Granulozytenanzahl. Schlussfolgerungen: Zwischen dem Ausmass der Mukositis und der Anzahl der neutrophilen Granulozyten in der Mundspuelfluessigkeit wurde tendenziell ein Zusammenhang beobachtet. Die starken Schwankungen der Messwerte verhindern jedoch die Verwendung dieses Parameters als Surrogat, um die radiogene Mukositis zu quantifizieren. Die Vermutung, dass eine Verminderung der neutrophilen Granulozyten in der Mundschleimhaut fuer die Entstehung der radiogenen Mukositis von Bedeutung ist, konnte nicht bestaetigt werden. (orig.)
The exact solution of a four-body Coulomb problem
Ray, Hasi
2018-03-01
The elastic collision between two H-like atoms utilizing an ab initio static-exchange model (SEM) in the center of mass (CM) frame considering the system as a four-body Coulomb problem where all the Coulomb interaction terms in the direct and exchange channels are treated exactly, is studied thoroughly. A coupled-channel methodology in momentum space is used to solve Lippman-Schwinger equation following the integral approach. The new SEM code [Ray, Pramana 83, 907 (2014)] in which the Born-Oppenheimer (BO) scattering amplitude acts as input to derive the SEM amplitude using partial wave analysis, is utilized to study the s-, p-, d-wave elastic phase shifts and the corresponding partial cross sections. An augmented-Born approximation is used to include the contribution of higher partial waves more accurately to determine the total/integrated elastic cross sections. The effective range theory is used to determine the scattering lengths and effective ranges in the s-wave elastic scattering. The systems studied are Ps-Ps, Ps-Mu, Ps-H, Ps-D, Ps-T, Mu-Mu, Mu-H, Mu-D, Mu-T, H-H, H-D, H-T, D-D, D-T, T-T. The SEM includes the non-adiabatic short-range effects due to exchange. The MSEM code [Ray, Pramana 83, 907 (2014)] is used to study the effect of the long-range van der Waals interaction due to induced dipole polarizabilities of the atoms in H(1s)-H(1s) elastic collision. The dependence of scattering length on the reduced mass of the system and the dependence of scattering length on the strength of long-range van der Waals interaction that varies with the minimum interatomic distance are observed. Contribution to the Topical Issue "Low Energy Positron and Electron Interactions", edited by James Sullivan, Ron White, Michael Bromley, Ilya Fabrikant, and David Cassidy.
Exclusion of nuclear forces in heavy-ion Coulomb excitation and Coulomb fission experiments
International Nuclear Information System (INIS)
Neese, R.E.; Guidry, M.W.
1982-01-01
A simple prescription for estimating the energy at which nuclear forces begin to play a role in heavy-ion Coulomb excitation and Coulomb fission experiments is presented. The method differs from most commonly used recipes in accounting for projectile and target nucleus deformation effects. Using a single adjustable parameter the formula reproduces the energy for the onset of Coulomb-nuclear interference effects for a broad range of heavy-ion systems. It is suggested that most Coulomb fission experiments which have been done involve both Coulomb and nuclear excitation processes and should more properly be termed Coulomb-nuclear fission experiments
The Coulomb gap and low energy statistics for Coulomb glasses
International Nuclear Information System (INIS)
Glatz, Andreas; Vinokur, Valerii M; Bergli, Joakim; Kirkengen, Martin; Galperin, Yuri M
2008-01-01
We study the statistics of local energy minima in the configuration space of two-dimensional lattice Coulomb glasses with site disorder and the behavior of the Coulomb gap depending on the strength of random site energies. At intermediate disorder, i.e., when the typical strength of the disorder is of the same order as the nearest-neighbor Coulomb energy, the high energy tail of the distribution of the local minima is exponential. We furthermore analyze the structure of the local minima and show that most sites of the system have the same occupation numbers in all of these states. The density of states (DOS) shows a transition from the crystalline state at zero disorder (with a hard gap) to an intermediate, probably glassy state with a Coulomb gap. We analyze this Coulomb gap in some detail and show that the DOS deviates slightly from the traditional linear behavior in 2D. For finite systems these intermediate Coulomb gap states disappear for large disorder strengths and only a random localized state in which all electrons are in the minima of the random potential exists. Dedication: This paper is dedicated to Thomas Nattermann, our dearest friend, brilliant colleague, and outstanding teacher
Evaluation of the Coulomb logarithm using cutoff and screened Coulomb interaction potentials
International Nuclear Information System (INIS)
Ordonez, C.A.; Molina, M.I.
1994-01-01
The Coulomb logarithm is a fundamental plasma parameter which is commonly derived within the framework of the binary collision approximation. The conventional formula for the Coulomb logarithm, λ=ln Λ, takes into account a pure Coulomb interaction potential for binary collisions and is not accurate at small values (λ D in place of λ D (the Debye length) in the conventional formula for the Coulomb logarithm
Local gauge symmetry and confinement in quantum chromodynamics
International Nuclear Information System (INIS)
Bardeen, W.A.; Pearson, R.B.
1977-01-01
The nonabelian color gauge theory of quarks and gluons has been proposed as the basis for fundamental theory of hadrons. The features of this theory (quantum chromodynamics) are considered which lead to confinement. A transverse lattice formulation of the theory is also discussed, which is used as a basis for calculation of properties of the hadron bound states. The theory is quantized by eliminating the longitudinal degrees of freedom in favour of coulomb potential. Hadrons are formed as bound states of quarks and the symmetric phase gluons
Nuclear waste - where to go?; Atommuell - wohin?
Energy Technology Data Exchange (ETDEWEB)
Dornsiepen, Ulrich
2015-07-01
The question of the final di9sposal of nuclear waste is a problem of international importance. The solution of the problem is of increasing urgency; the discussion is controversial and implies a lot of emotions. In Germany there is consensus that the nuclear wastes have to be disposed within the country in deep geological formations. This kind of final disposal is predominantly a geological problem and has to be solved from the geological point of view. The geologist Ulrich Dornsiepen presents the problems of the final disposal in an objective way without ideology and generally understandable. Such a presentation is necessary since the public information and participation is demanded but the open geological questions and their scientific solutions are never explained for the public. [German] Die Frage der endgueltigen Lagerung von Atommuell ist ein Problem von nationaler Tragweite, dessen Loesung immer dringender wird, bisher aber sehr kontrovers diskutiert wird und mit vielen Emotionen verknuepft ist. Es besteht in Deutschland ein Konsens, diese Abfaelle innerhalb der Landesgrenzen dauerhaft in tief liegenden Gesteinsschichten abzulagern. Diese Art der Endlagerung ist aber in erster Linie ein geologisches Problem und so auch nur von geologischer Seite her zu loesen. Daher stellt der Geologe Ulrich Dornsiepen die Problematik der Endlagerung objektiv, ideologiefrei und allgemein verstaendlich dar. Ein solches Hoerbuch ist dringend noetig, da zwar die Information und Beteiligung breiter, betroffener Bevoelkerungsteile eingefordert, aber niemals versucht wird, die offenen geologischen Fragen und ihre wissenschaftliche Loesung verstaendlich zu machen.
Double gauge invariance and covariantly-constant vector fields in Weyl geometry
Kassandrov, Vladimir V.; Rizcallah, Joseph A.
2014-08-01
The wave equation and equations of covariantly-constant vector fields (CCVF) in spaces with Weyl nonmetricity turn out to possess, in addition to the canonical conformal-gauge, a gauge invariance of another type. On a Minkowski metric background, the CCVF system alone allows us to pin down the Weyl 4-metricity vector, identified herein with the electromagnetic potential. The fundamental solution is given by the ordinary Lienard-Wiechert field, in particular, by the Coulomb distribution for a charge at rest. Unlike the latter, however, the magnitude of charge is necessarily unity, "elementary", and charges of opposite signs correspond to retarded and advanced potentials respectively, thus establishing a direct connection between the particle/antiparticle asymmetry and the "arrow of time".
6d, Coulomb branch anomaly matching
Intriligator, Kenneth
2014-10-01
6d QFTs are constrained by the analog of 't Hooft anomaly matching: all anomalies for global symmetries and metric backgrounds are constants of RG flows, and for all vacua in moduli spaces. We discuss an anomaly matching mechanism for 6d theories on their Coulomb branch. It is a global symmetry analog of Green-Schwarz-West-Sagnotti anomaly cancellation, and requires the apparent anomaly mismatch to be a perfect square, . Then Δ I 8 is cancelled by making X 4 an electric/magnetic source for the tensor multiplet, so background gauge field instantons yield charged strings. This requires the coefficients in X 4 to be integrally quantized. We illustrate this for theories. We also consider the SCFTs from N small E8 instantons, verifying that the recent result for its anomaly polynomial fits with the anomaly matching mechanism.
Energy Technology Data Exchange (ETDEWEB)
Lehmann, K.
2001-07-01
Risks have become a central problem of our time, as is reflected in concepts like 'society at risk' and 'anti-technological attitude', in group protest against risks and against those who cause them, and last but not least in the critical attitude of the media. Against this background, organisations must needs enter the public discussion and be able to communicate professionally and convincingly in order to ensure their own success and further existence. The book describes the basic problems of risk research and risk communications and discusses inhowfar, and how, public relations strategies and instruments can help here. [German] Risiken werden verstaerkt zum Problem unserer Zeit. Das belegen nicht nur Begriffe wie 'Risikogesellschaft' und 'Technikfeindlichkeit', die in letzter Zeit an Bedeutung gewonnen haben, sondern auch und vor allem nachhaltige Proteste von engagierten Gruppierungen gegen Risiken und deren Verursacher oder auch die kritische Berichterstattung der Medien. Vor diesem Hintergrund ist es fuer Organisationen erforderlich, in die oeffentliche Auseinandersetzung um Risiken einzusteigen und hier professionell und ueberzeugend zu kommunizieren, um den Organisationserfolg und Organisationsbestand zu sichern. Die vorliegende Arbeit beschreibt die Grundprobleme der Risikoforschung und Risikokommunikation und diskutiert, ob und inwieweit Public Relations bei der Loesung dieser Probleme helfen koennen, da insbesondere Public Relations gezielt Strategien und Instrumente nutzen, um beispielsweise den Wissensstand der Oeffentlichkeit zu verbessern und den Dialog mit relevanten Teiloeffentlichkeiten zu foerdern. (orig.)
Extended Hamiltonian formalism of the pure space-like axial gauge Schwinger model
International Nuclear Information System (INIS)
Nakawaki, Yuji; Mccartor, Gary
2001-01-01
We demonstrate that pure space-like axial gauge quantizations of gauge fields can be constructed in ways that are free from infrared divergences. To do so, we must extend the Hamiltonian formalism to include residual gauge fields. We construct an operator solution and an extended Hamiltonian of the pure space-like axial gauge Schwinger model. We begin by constructing an axial gauge formation in auxiliary coordinates, x μ =(x + , x - ), where x + =x 0 sinθ + x 1 cosθ, x - =x 0 cosθ - x 1 sinθ, and we take A=A 0 cosθ + A 1 sin θ=0 as the gauge fixing condition. In the region 0 - as the evolution parameter and construct a traditional canonical formulation of the temporal gauge Schwinger model in which residual gauge fields dependent only on x + are static canonical variables. Then we extrapolate the temporal gauge operator solution into the axial region, π / 4 + is taken as the evolution parameter. In the axial region we find that we have to take the representation of the residual gauge fields realizing the Mandelstam-Leibbrandt prescription in order for the infrared divergences resulting from (∂) -1 to be canceled by corresponding ones resulting from the inverse of the hyperbolic Laplace operator. We overcome the difficulty of constructing the Hamiltonian for the residual gauge fields by employing McCartor and Robertson's method, which gives us a term integrated over x - =constant. Finally, by taking the limit θ→π / 2 - 0, we obtain an operator solution and the Hamiltonian of the axial gauge (Coulomb gauge) Schwinger model in ordinary coordinates. That solution includes auxiliary fields, and the representation space is of indefinite metric, providing further evidence that 'physical' gauges are no more physical than 'unphysical' gauges. (author)
BPS/CFT Correspondence III: Gauge Origami Partition Function and qq-Characters
Nekrasov, Nikita
2018-03-01
We study generalized gauge theories engineered by taking the low energy limit of the Dp branes wrapping {X × {T}^{p-3}}, with X a possibly singular surface in a Calabi-Yau fourfold Z. For toric Z and X the partition function can be computed by localization, making it a statistical mechanical model, called the gauge origami. The random variables are the ensembles of Young diagrams. The building block of the gauge origami is associated with a tetrahedron, whose edges are colored by vector spaces. We show the properly normalized partition function is an entire function of the Coulomb moduli, for generic values of the {Ω} -background parameters. The orbifold version of the theory defines the qq-character operators, with and without the surface defects. The analytic properties are the consequence of a relative compactness of the moduli spaces M({ěc n}, k) of crossed and spiked instantons, demonstrated in "BPS/CFT correspondence II: instantons at crossroads, moduli and compactness theorem".
Mirror symmetry in three-dimensional gauge theories, quivers and D-branes
International Nuclear Information System (INIS)
De Boer, J.; Ernest Orlando Lawrence Berkeley Nat. Lab., CA; Hori, K.; Ernest Orlando Lawrence Berkeley Nat. Lab., CA; Ooguri, H.; Ernest Orlando Lawrence Berkeley Nat. Lab., CA; Oz, Y.; Ernest Orlando Lawrence Berkeley Nat. Lab., CA
1997-01-01
We construct and analyze dual N=4 supersymmetric gauge theories in three dimensions with unitary and symplectic gauge groups. The gauge groups and the field content of the theories are encoded in quiver diagrams. The duality exchanges the Coulomb and Higgs branches and the Fayet-Iliopoulos and mass parameters. We analyze the classical and the quantum moduli spaces of the theories and construct an explicit mirror map between the mass parameters and the Fayet-Iliopoulos parameters of the dual. The results generalize the relation between ALE spaces and moduli spaces of SU(n) and SO(2n) instantons. We interpret some of these results from the string theory viewpoint, for SU(n) by analyzing T-duality and extremal transitions in type II string compactifications, for SO(2n) by using D-branes as probes. Finally, we make a proposal for the moduli space of vacua of these theories in the absence of matter. (orig.)
Fuzzy bags, Polyakov loop and gauge/string duality
Directory of Open Access Journals (Sweden)
Zuo Fen
2014-01-01
Full Text Available Confinement in SU(N gauge theory is due to the linear potential between colored objects. At short distances, the linear contribution could be considered as the quadratic correction to the leading Coulomb term. Recent lattice data show that such quadratic corrections also appear in the deconfined phase, in both the thermal quantities and the Polyakov loop. These contributions are studied systematically employing the gauge/string duality. “Confinement” in N${\\cal N}$ = 4 SU(N Super Yang-Mills (SYM theory could be achieved kinematically when the theory is defined on a compact space manifold. In the large-N limit, deconfinement of N${\\cal N}$ = 4 SYM on S3${{\\Bbb S}^3}$ at strong coupling is dual to the Hawking-Page phase transition in the global Anti-de Sitter spacetime. Meantime, all the thermal quantities and the Polyakov loop achieve significant quadratic contributions. Similar results can also be obtained at weak coupling. However, when confinement is induced dynamically through the local dilaton field in the gravity-dilaton system, these contributions can not be generated consistently. This is in accordance with the fact that there is no dimension-2 gauge-invariant operator in the boundary gauge theory. Based on these results, we suspect that quadratic corrections, and also confinement, should be due to global or non-local effects in the bulk spacetime.
Coulomb interaction in multiple scattering theory
International Nuclear Information System (INIS)
Ray, L.; Hoffmann, G.W.; Thaler, R.M.
1980-01-01
The treatment of the Coulomb interaction in the multiple scattering theories of Kerman-McManus-Thaler and Watson is examined in detail. By neglecting virtual Coulomb excitations, the lowest order Coulomb term in the Watson optical potential is shown to be a convolution of the point Coulomb interaction with the distributed nuclear charge, while the equivalent Kerman-McManus-Thaler Coulomb potential is obtained from an averaged, single-particle Coulombic T matrix. The Kerman-McManus-Thaler Coulomb potential is expressed as the Watson Coulomb term plus additional Coulomb-nuclear and Coulomb-Coulomb cross terms, and the omission of the extra terms in usual Kerman-McManus-Thaler applications leads to negative infinite total reaction cross section predictions and incorrect pure Coulomb scattering limits. Approximations are presented which eliminate these anomalies. Using the two-potential formula, the full projectile-nucleus T matrix is separated into two terms, one resulting from the distributed nuclear charge and the other being a Coulomb distorted nuclear T matrix. It is shown that the error resulting from the omission of the Kerman-McManus-Thaler Coulomb terms is effectively removed when the pure Coulomb T matrix in Kerman-McManus-Thaler is replaced by the analogous quantity in the Watson approach. Using the various approximations, theoretical angular distributions are obtained for 800 MeV p+ 208 Pb elastic scattering and compared with experimental data
Energy Technology Data Exchange (ETDEWEB)
Hoehn, Eduard [Eawag, Eidgenoessische Anstalt fuer Wasserversorgung, Abwasserreinigung und Gewaesserschutz, Duebendorf (Switzerland)
2007-03-15
ersten Hochwasser bewirkten die Renaturierungsmassnahmen eine Aufweitung des Ufers und eine Verringerung der Fliessdistanz des infiltrierenden Wassers zu den Rohren. Im Vergleich mit Radonmessungen vor diesen Massnahmen, resultierten Messungen, die 16 Tage nach einem zweiten Hochwasser durchgefuehrt wurden, in einer Verringerung der Radon-Grundwasseralter auf dieser Strecke, dies als Folge der Verringerung der Fliessdistanzen. Die Zahlen von autochthonen und coliformen Bakterien stiegen bereits bei einer Messung nach der Befreiung des Ufers und dann besonders bei einer Messung einen Tag nach dem ersten Hochwasser. Damit stuetzen diese Befunde die Interpretation der Radonmessungen. Auf die Trinkwasserqualitaet wirkte sich die Flussaufweitung hingegen bislang nicht aus. Solche Untersuchungen leisten einen Beitrag zur Loesung des raumwirksamen Nutzungskonflikts zwischen Flussrenaturierung und Grundwassernutzung als Trinkwasser. (orig.)
Electron transport in gold colloidal nanoparticle-based strain gauges
Moreira, Helena; Grisolia, Jérémie; Sangeetha, Neralagatta M.; Decorde, Nicolas; Farcau, Cosmin; Viallet, Benoit; Chen, Ke; Viau, Guillaume; Ressier, Laurence
2013-03-01
A systematic approach for understanding the electron transport mechanisms in resistive strain gauges based on assemblies of gold colloidal nanoparticles (NPs) protected by organic ligands is described. The strain gauges were fabricated from parallel micrometer wide wires made of 14 nm gold (Au) colloidal NPs on polyethylene terephthalate substrates, elaborated by convective self-assembly. Electron transport in such devices occurs by inter-particle electron tunneling through the tunnel barrier imposed by the organic ligands protecting the NPs. This tunnel barrier was varied by changing the nature of organic ligands coating the nanoparticles: citrate (CIT), phosphines (BSPP, TDSP) and thiols (MPA, MUDA). Electro-mechanical tests indicate that only the gold NPs protected by phosphine and thiol ligands yield high gauge sensitivity. Temperature-dependent resistance measurements are explained using the ‘regular island array model’ that extracts transport parameters, i.e., the tunneling decay constant β and the Coulomb charging energy EC. This reveals that the Au@CIT nanoparticle assemblies exhibit a behavior characteristic of a strong-coupling regime, whereas those of Au@BSPP, Au@TDSP, Au@MPA and Au@MUDA nanoparticles manifest a weak-coupling regime. A comparison of the parameters extracted from the two methods indicates that the most sensitive gauges in the weak-coupling regime feature the highest β. Moreover, the EC values of these 14 nm NPs cannot be neglected in determining the β values.
Noll, Ellis; Koehlinger, Mervin; Kowalski, Ludwik; Swackhamer, Gregg
1998-01-01
Describes the use of a computer-linked camera to demonstrate Coulomb's law. Suggests a way of reducing the difficulties in presenting Coulomb's law by teaching the inverse square law of gravity and the inverse square law of electricity in the same unit. (AIM)
Efficient evaluation of the Coulomb force in the Gaussian and finite-element Coulomb method.
Kurashige, Yuki; Nakajima, Takahito; Sato, Takeshi; Hirao, Kimihiko
2010-06-28
We propose an efficient method for evaluating the Coulomb force in the Gaussian and finite-element Coulomb (GFC) method, which is a linear-scaling approach for evaluating the Coulomb matrix and energy in large molecular systems. The efficient evaluation of the analytical gradient in the GFC is not straightforward as well as the evaluation of the energy because the SCF procedure with the Coulomb matrix does not give a variational solution for the Coulomb energy. Thus, an efficient approximate method is alternatively proposed, in which the Coulomb potential is expanded in the Gaussian and finite-element auxiliary functions as done in the GFC. To minimize the error in the gradient not just in the energy, the derived functions of the original auxiliary functions of the GFC are used additionally for the evaluation of the Coulomb gradient. In fact, the use of the derived functions significantly improves the accuracy of this approach. Although these additional auxiliary functions enlarge the size of the discretized Poisson equation and thereby increase the computational cost, it maintains the near linear scaling as the GFC and does not affects the overall efficiency of the GFC approach.
Diffusion in Coulomb crystals.
Hughto, J; Schneider, A S; Horowitz, C J; Berry, D K
2011-07-01
Diffusion in Coulomb crystals can be important for the structure of neutron star crusts. We determine diffusion constants D from molecular dynamics simulations. We find that D for Coulomb crystals with relatively soft-core 1/r interactions may be larger than D for Lennard-Jones or other solids with harder-core interactions. Diffusion, for simulations of nearly perfect body-centered-cubic lattices, involves the exchange of ions in ringlike configurations. Here ions "hop" in unison without the formation of long lived vacancies. Diffusion, for imperfect crystals, involves the motion of defects. Finally, we find that diffusion, for an amorphous system rapidly quenched from Coulomb parameter Γ=175 to Coulomb parameters up to Γ=1750, is fast enough that the system starts to crystalize during long simulation runs. These results strongly suggest that Coulomb solids in cold white dwarf stars, and the crust of neutron stars, will be crystalline and not amorphous.
Energy Technology Data Exchange (ETDEWEB)
Gochermann, Josef [Hochschule Osnabrueck, Lingen (Germany). Professur Marketing und Technologiemanagement
2017-07-15
The growth in renewable energy systems is stagnating. Is the energy transition bogged down? Is the transition to the new energy world over-regulated? In addition to the regulation of the large systems at the national level, the energy users need more scope and flexibility at regional and on individual level. The present article deals with the most important criticisms regarding the energy transition and provides references on their solution. [German] Der Zuwachs an erneuerbaren Energieanlagen stagniert. Ist die Energiewende festgefahren? Wird der Uebergang in die neue Energiewelt ueberreguliert? Neben der Regulation der grossen Systeme auf nationaler Ebene braucht die Energiewende mehr Freiraum und Flexibilitaet auf regionaler und auf individualer Ebene. Der vorliegende Artikel greift die wichtigsten Kritikpunkte in Bezug auf die Energiewende auf und gibt Hinweise zu deren Loesung.
Typeinddeling og kvalitetselementer for marine områder i Danmark
DEFF Research Database (Denmark)
Nielsen, K.; Sømod, B.; Christiansen, T.
betragtes som udkast til en fremtidig vejledning for planlægning af vandkvaliteten i marine områder. INDLEDNING: Vandrammedirektivet har til formål at forebygge forurening og forringelse af den økologiske tilstand samt at danne grundlag for restaurering af vandområder med henblik på at opnå en god økologisk...... collection For many years the water stage has been registered by means of manual readings of a water level gauge placed at many of the sta-tions, but also automatic chart recorders have been in operation since the beginning of the 20th century. Nowadays, registrations are nor-mally performed by dataloggers...
Hyperspherical Coulomb spheroidal basis in the Coulomb three-body problem
International Nuclear Information System (INIS)
Abramov, D. I.
2013-01-01
A hyperspherical Coulomb spheroidal (HSCS) representation is proposed for the Coulomb three-body problem. This is a new expansion in the set of well-known Coulomb spheroidal functions. The orthogonality of Coulomb spheroidal functions on a constant-hyperradius surface ρ = const rather than on a constant-internuclear-distance surface R = const, as in the traditional Born-Oppenheimer approach, is a distinguishing feature of the proposed approach. Owing to this, the HSCS representation proves to be consistent with the asymptotic conditions for the scattering problem at energies below the threshold for three-body breakup: only a finite number of radial functions do not vanish in the limit of ρ→∞, with the result that the formulation of the scattering problem becomes substantially simpler. In the proposed approach, the HSCS basis functions are considerably simpler than those in the well-known adiabatic hyperspherical representation, which is also consistent with the asymptotic conditions. Specifically, the HSCS basis functions are completely factorized. Therefore, there arise no problems associated with avoided crossings of adiabatic hyperspherical terms.
Energy Technology Data Exchange (ETDEWEB)
Schirmer, U.; Krueger, H.; Puch, K.H. [VGB Technische Vereinigung der Grosskraftwerksbetreiber e.V., Essen (Germany)
1998-09-01
Reststoffen und Abfaellen zwangslaeufig. Sie wurde in vielen VGB-Mitgliedsunternehmen erwogen und bereits in mehreren Faellen konkret geprueft. Dabei beruecksichtigte die Bearbeitung folgende grundsaetzlichen Positionen: - Die VGB-Mitgliedsunternehmen sind bereit, sich an der Loesung der oben genannten Aufgaben zu beteiligen, soweit dies ohne Beeintraechtigung ihrer Verpflichtungen zur Energieversorgung moeglich ist. - Die Uebernahme derartiger Verpflichtungen kann nur unter Wahrung der genehmigungsrechtlichen Voraussetzungen erfolgen. Dies gilt fuer die Qualitaet und die anfallenden Mengen der zu uebernehmenden Abfaelle, fuer die Emissionen und fuer die Entsorgung der Verbrennungsrueckstaende. - Der Betrieb von Kraftwerksanlagen beinhaltet eine weitgehende Verwertung der anfallenden Prozessrueckstaende, die nach Moeglichkeit durch die Mitverbrennung nicht beeintraechtigt werden darf. - Die technische Aufgabe der Mitverbrennung von geeigneten Rueckstaenden und Abfaellen ist in der Regel loesbar. Sie stellt eine Alternative und Ergaenzung zu reinen Abfallverwertungsanlagen oder Anlagen zur Verwertung von geeigneten Rueckstaenden dar. Darueber hinaus sind einige Unternehmen daran interessiert, durch Abschoepfen der Zuzahlungen fuer diese Abfallverwertung wirtschaftliche Vorteile zu erlangen. Eine VGB-Arbeitsgruppe hat sich bereits 1990 bis 1992 auf dieser Basis mit der Mitverbrennung auseinandergesetzt und die Grundlagen fuer die im folgenden dargestellten Ueberlegungen erarbeitet. (orig.)
Integral equation for Coulomb problem
International Nuclear Information System (INIS)
Sasakawa, T.
1986-01-01
For short range potentials an inhomogeneous (homogeneous) Lippmann-Schwinger integral equation of the Fredholm type yields the wave function of scattering (bound) state. For the Coulomb potential, this statement is no more valid. It has been felt difficult to express the Coulomb wave function in a form of an integral equation with the Coulomb potential as the perturbation. In the present paper, the author shows that an inhomogeneous integral equation of a Volterra type with the Coulomb potential as the perturbation can be constructed both for the scattering and the bound states. The equation yielding the binding energy is given in an integral form. The present treatment is easily extended to the coupled Coulomb problems
Holographic repulsion and confinement in gauge theory
Husain, Viqar; Kothawala, Dawood
2013-02-01
We show that for asymptotically anti-de Sitter (AdS) backgrounds with negative energy, such as the AdS soliton and regulated negative-mass AdS-Schwarzshild metrics, the Wilson loop expectation value in the AdS/CFT conjecture exhibits a Coulomb to confinement transition. We also show that the quark-antiquark (q \\bar{q}) potential can be interpreted as affine time along null geodesics on the minimal string worldsheet and that its intrinsic curvature provides a signature of transition to confinement phase. Our results suggest a generic (holographic) relationship between confinement in gauge theory and repulsive gravity, which in turn is connected with singularity avoidance in quantum gravity. Communicated by P R L V Moniz
Expansions for Coulomb wave functions
Boersma, J.
1969-01-01
In this paper we derive a number of expansions for Whittaker functions, regular and irregular Coulomb wave functions. The main result consists of a new expansion for the irregular Coulomb wave functions of orders zero and one in terms of regular Coulomb wave functions. The latter expansions are
International Nuclear Information System (INIS)
Kar, S.; Ho, Y.K.
2009-01-01
We have investigated the doubly excited 1 D e resonance states of Ps - interacting with pure Coulomb and screened Coulomb (Yukawa) potentials employing highly correlated wave functions. For pure Coulomb interaction, in the framework of stabilization method and complex coordinate rotation method we have obtained two resonances below the n = 2 threshold of the Ps atom. For screened Coulomb interaction, we employ the stabilization method to extract resonance parameters. Resonance energies and widths for the 1 D e resonance states of Ps - for different screening parameter ranging from infinity (pure Coulomb case) to a small value are also reported. (author)
Deconfinement phase transition in the Hamiltonian approach to Yang–Mills theory in Coulomb gauge
Directory of Open Access Journals (Sweden)
Reinhardt H.
2014-04-01
Full Text Available Recent results obtained for the deconfinement phase transition within the Hamiltonian approach to Yang–Mills theory are reviewed. Assuming a quasiparticle picture for the grand canonical gluon ensemble the thermal equilibrium state is found by minimizing the free energy with respect to the quasi-gluon energy. The deconfinement phase transition is accompanied by a drastic change of the infrared exponents of the ghost and gluon propagators. Above the phase transition the ghost form factor remains infrared divergent but its infrared exponent is approximately halved. The gluon energy being infrared divergent in the confined phase becomes infrared finite in the deconfined phase. Furthermore, the effective potential of the order parameter for confinement is calculated for SU(N Yang–Mills theory in the Hamiltonian approach by compactifying one spatial dimension and using a background gauge fixing. In the simplest truncation, neglecting the ghost and using the ultraviolet form of the gluon energy, we recover the Weiss potential. From the full non-perturbative potential (with the ghost included we extract a critical temperature of the deconfinement phase transition of 269 MeV for the gauge group SU(2 and 283 MeV for SU(3.
Coulomb potentials between spherical heavy ions
International Nuclear Information System (INIS)
Iwe, H.
1982-01-01
The Coulomb interaction between spherical nuclei having arbitrary radial nuclear charge distributions is calculated. All these realistic Coulomb potentials are given in terms of analytical expressions and are available for immediate application. So in no case a numerical computation of the Coulomb integral is required. The parameters of the charge distributions are taken from electron scattering analysis. The Coulomb self-energies of the charge distributions used are also calculated analytically in a closed form. For a number of nucleus-nucleus pairs, the Coulomb potentials derived from realistic charge distributions are compared with those normally used in various nucleus-nucleus optical model calculations. In this connection a detailed discussion of the problem how to choose consistently Coulomb parameters for different approximations is given. (orig.)
Directory of Open Access Journals (Sweden)
Massimo Maria Brignoli
2012-08-01
Full Text Available Die Tradition der amerikanischen Landschaftarchitektur hatt aus Boston ein Planungsexperiment gemacht. Das Emerald Necklace, eine echte Ikone der Landschaftsarchitektur, bezeugt immer noch wirkungsvoll, wie die Landschaftsplanung die Struktur moderner Grossstaedte mit Raum zum wohnen staerken kann. Heute muss die Stadt mit ihren von der Central Artery hervorgerufenen Wunden fertigwerden, mit Risultaten, die wahrscheinlich nicht der Groesse ihrer Geschichte entsprechen. Der teilweise Erfolg der Rose Kennedy Greenway macht die Notwendigkeit klar, die Regelung fuer die Planung der offenen Gebiete neu zu bestimmen.
A Coulomb-Like Off-Shell T-Matrix with the Correct Coulomb Phase Shift
International Nuclear Information System (INIS)
Oryu, Shinsho; Watanabe, Takashi; Hiratsuka, Yasuhisa; Togawa, Yoshio
2017-01-01
We confirm the reliability of the well-known Coulomb renormalization method (CRM). It is found that the CRM is only available for a very-long-range screened Coulomb potential (SCP). However, such an SCP calculation in momentum space is considerably difficult because of the cancellation of significant digits. In contrast to the CRM, we propose a new method by using an on-shell equivalent SCP and the rest term. The two-potential theory with r-space is introduced, which defines fully the off-shell Coulomb amplitude. (author)
Energy Technology Data Exchange (ETDEWEB)
Dierks, G. [Fa. Jaeggi/Guentner (Schweiz) AG, Trimbach (Switzerland)
2000-03-01
There are several air-cooled forced-circulation cooling systems for heat removal from refrigeration systems. Optimum solutions should not be selected on the basis of the cost factor alone; an integrative approach should be used instead. An exemplary investigation is presented. [German] Fuer die Waermeabfuhr aus kaeltetechnischen Anlagen stehen verschiedene luftgekuehlte, zwangsbelueftete Rueckkuehlsysteme zur Verfuegung. Die Auswahl des Systems ist oft von kurzfristigem Kostendenken gepraegt, was in technischer und wirtschaftlicher Hinsicht aber nicht immer der optimalen Loesung entspricht. Erst die genauere Kenntnis der verschiedenen Systeme und eine ganzheitliche Betrachtungsweise ermoeglichen die optimale Wahl fuer den einzelnen Fall. Die hier praesentierte Untersuchung wird anhand eines konkreten Falls dargestellt, wobei Preise und technische Produktdaten auf realen Anfragen beruhen. Der Autor ist um objetive Bewertung bemueht, der Leser moege aber selbst urteilen. (orig./AKF)
New torsion black hole solutions in Poincaré gauge theory
Energy Technology Data Exchange (ETDEWEB)
Cembranos, Jose A.R.; Valcarcel, Jorge Gigante, E-mail: cembra@fis.ucm.es, E-mail: jorgegigante@ucm.es [Departamento de Física Teórica I, Universidad Complutense de Madrid, Av. Complutense s/n, E-28040 Madrid (Spain)
2017-01-01
We derive a new exact static and spherically symmetric vacuum solution in the framework of the Poincaré gauge field theory with dynamical massless torsion. This theory is built in such a form that allows to recover General Relativity when the first Bianchi identity of the model is fulfilled by the total curvature. The solution shows a Reissner-Nordström type geometry with a Coulomb-like curvature provided by the torsion field. It is also shown the existence of a generalized Reissner-Nordström-de Sitter solution when additional electromagnetic fields and/or a cosmological constant are coupled to gravity.
Anyons, spin, and statistics in (2+1)-dimensional U(1)-scalar Chern-Simons gauge field theory
International Nuclear Information System (INIS)
Graziano, E.; Rothe, K.D.
1994-01-01
We present a detailed analysis of the quantum field theory of a Chern-Simons field coupled minimally to massive charged bosonic matter. This analysis is carried out in the Coulomb and covariant gauges. Some aspects concerning the transformation law of the fields under Poincare transformations are clarified. Emphasis is placed on gauge-invariant operators. The order and disorder operators are constructed from their dual algebra. The order operator is shown to obey anyonic statistics. The correlator of the disorder operator is computed in the large boson-mass limit, and the corresponding cluster properties are discussed. In the absence of a symmetry-breaking Higgs potential, there is no evidence for the ground state being anyonic
International Nuclear Information System (INIS)
Bes, D.R.
1984-01-01
The history of the development of quantum field theory for treating coupling between phonons and fermions are summarized. These perturbative theories are applied introducing concept of gauge invariance for the problem of rotation nuclei. (L.C.) [pt
Wilson loops from multicentre and rotating branes, mass gaps and phase structure in gauge theories
Brandhuber, A.
1999-01-01
Within the AdS/CFT correspondence we use multicentre D3-brane metrics to investigate Wilson loops and compute the associated heavy quark-antiquark potentials for the strongly coupled SU(N) super-Yang-Mills gauge theory, when the gauge symmetry is broken by the expectation values of the scalar fields. For the case of a uniform distribution of D3-branes over a disc, we find that there exists a maximum separation beyond which there is no force between the quark and the antiquark, i.e. the screening is complete. We associate this phenomenon with the possible existence of a mass gap in the strongly coupled gauge theory. In the finite-temperature case, when the corresponding supergravity solution is a rotating D3-brane solution, there is a class of potentials interpolating between a Coulombic and a confining behaviour. However, above a certain critical value of the mass parameter, the potentials exhibit a behaviour characteristic of statistical systems undergoing phase transitions. The physical path preserves the c...
Energy Technology Data Exchange (ETDEWEB)
Stark, C.; Horn, R.; Hetfleisch, J.; Fricke, J.
2003-02-25
Solar energy can be used in buildings via use of transparent insulations. But thereby problems occur, like overheating of building walls in summer and heat losses in the cold season. To solve these problems ZAE Bayern has designed and optimized the switchable insulation SWD, the thermal conductivity of which can be changed from highly insulating to conducting. A computer routine was developed to calculate and to optimize the heat gains. The SWD is switched by desorbing/adsorbing as small amount of hydrogen gas. Desorption is facilitated with an electric heating element. The thermal conductivity of the filling can be varied by about a factor of 40. Several SWD-modules were produced and installed in an outside measuring facility. The heat gains and the durability were investigated for three years. The results of the simulation could be verified and ageing did not occur. For an optimal system the heat gains are in the range of 150 kWh/(m{sup 2}a). The mounting of these panels at south facades is simple, especially for post bolt systems. Contrary to transparent systems the loss of heat in winter is very small and the overheating of the walls behind the SWD in summer can be avoided. (orig.) [German] Zur Nutzung der Sonnenenergie in Gebaeuden werden bisher transparente Waermedaemmsysteme eingebaut, die jedoch oft mit Problemen wie Wandueberhitzung im Sommer und Waermeverlusten in der kalten Jahreszeit behaftet sind. Zur Loesung dieser Probleme wurde am ZAE Bayern eine schaltbare Waermedaemmung entwickelt und optimiert, deren Daemmeigenschaft je nach Sonneneinstrahlung und Waermebedarf variiert werden kann. Es wurde ein Programm entwickelt, mit dem die Waermegewinne berechnet und optimiert werden koennen. Die Schaltbarkeit wird durch einen Getter ermoeglicht, der eine ungefaehrliche Menge Wasserstoffgas reversibel aufnehmen und abgeben kann. Die Wasserstoff-Austreibung erfolgt mittels elektrischer Heizung und veraendert die Waermeleitfaehigkeit der Fuellung um einen
Coulomb correction calculations of pp Bremsstrahlung
International Nuclear Information System (INIS)
Katsogiannis, A.; Amos, K.; Jetter, M.; von Geramb, H.V.
1994-01-01
The effects of the Coulomb interaction upon the photon cross section and analyzing power from pp Bremsstrahlung have been studied in detail. Off-shell properties of the Coulomb T matrices have been considered but the associated, Coulomb modified, hadronic T matrices are important elements in any analyses of low energy, forward proton scattering data. At the lowest energy considered (5 MeV), the full calculations gave cross sections that were half the size of those found without Coulomb effects or with a simple model approximation to them. With increasing energy, the cross sections varied to those characteristic of magnetic interaction dominance and the specific differences due to Coulomb effects diminished. 47 refs., 7 figs
Inflationary magnetogenesis, derivative couplings and relativistic Van der Waals interactions
Giovannini, Massimo
2015-01-01
When the gauge fields have derivative couplings to scalars, like in the case of the relativistic theory of Van der Waals (or Casimir-Polder) interactions, conformal invariance is broken but the magnetic and electric susceptibilities are not bound to coincide. We analyze the formation of large-scale magnetic fields in slow-roll inflation and find that they are generated at the level of a few hundredths of a nG and over typical length scales between few Mpc and $100$ Mpc. Using a new time parametrization that reduces to conformal time but only for coincident susceptibilities, the gauge action is quantized while the evolution equations of the corresponding mode functions are more easily solvable. The power spectra depend on the normalized rates of variation of the two susceptibilities (or of the corresponding gauge couplings) and on the absolute value of their ratio at the beginning of inflation. We pin down explicit regions in the parameter space where all the physical requirements (i.e. the backreaction constr...
Dynamical mechanism of symmetry breaking and particle mass generation in gauge field theories
International Nuclear Information System (INIS)
Miranskij, V.A.; Fomin, P.I.
1985-01-01
The dynamics of the spotaneous symmetry breaking and the particle mass generation in gauge theories with no fundamental scalar fields is considered. The emphasis is on the consideration of the symmetry breaking mechanism connected with the dynamics of the supercritical Coulomb-like forces caused by the gauge boson exchange between fermions. This mechanism is applied to different gauge theories, in particular, to the description of the spontaneous chira symmetry breaking in quantum chromodynamics. The mass relations for pseudoscalar meson nonet are obtained and it is shown that this mechanism resuls in the dynamical realisation of the hypothesis of the partial conservation of the axial-vector currents. The qualitative description of scalar mesons is given. The nature of the ultraviolet divergencies in quantum electrodynamics (QED) is investigated from the viewpoint of the dynamics of the fermion mass generation. The mechanism of the appearance of the additional (in comparison with perturbation theory) ultraviolet divergencies in QED with large bare coupling constant is indicated. The physical phenomenon underlying this mechanism is identified as the field theory analogue of the quantum mechanical ''fall into the centre'' (collapse) phenomenon. The similr phenomenon is shown to take place in some two-dimensional quantum field models. The dynamics of the bifermion condensates formation in tumblin gauge theories is briefly discussed
Energy Technology Data Exchange (ETDEWEB)
Holzer, J [Bayernwerk AG, Muenchen (Germany)
1993-12-31
This report throws a critical look at the targets and guidelines aimed at by the EC Commission in order to change the present regulative frame of electricity supply. Particularly the difference between the German, French and British situation is shown. In the opinion of German electric utilities the principle of closed supply areas has to be sticked to. Finally the necessity is emphasized to use energy policy to solve quickly some problems in order to improve the standing of German electric utilities. (UA) [Deutsch] Der Vortrag beinhaltet eine kritische Auseinandersetzung mit den von der EG-Kommision verfolgten Zielen und Richtlinien zur Aenderung des bisherigen Ordnungsrahmens in der Elektrizitaetsversorgung. Insbesondere werden die Unterschiede im Vergleich zwischen deutschen, franzoesischen und englischen Verhaeltnissen herausgestellt. Nach Ausicht der deutschen EVUs muss das Prinzip der geschlossenen Versorgungsgebiete erhalten bleiben. Abschliessend wird die Forderung unterstrichen, die Loesung einiger Probleme durch die Energiepolitik voranzutreiben, um die Position der deutschen Elektrizitaetsversorgung zu verbessern. (UA)
Der Fachbereich Fertigungstechnik der Zukunft
DEFF Research Database (Denmark)
Alting, Leo
1998-01-01
Forscher sowie für eine industrielle Zusammenarbeit/Beratung eine attraktive Umgebung zu bieten.Im vorliegenden Papier wird ein internes Entwicklungsprojekt, genannt "Der Fachberich der Zukunft", beschrieben. Ausgehend von den Bedürfnissen und Erwartungen der Kunden (Studierende, Einrichtungen der...
International Nuclear Information System (INIS)
Huang Yongchang; Huo Qiuhong
2008-01-01
Using Faddeev-Senjanovic path integral quantization for constrained Hamilton system, we quantize SU(n) N=2 supersymmetric gauge field system with non-Abelian Chern-Simons topological term in 2+1 dimensions. We use consistency of Coulomb gauge condition to naturally deduce a new gauge condition. Furthermore, we obtain the generating functional of Green function in phase space, deduce the angular momentum based on the global canonical Noether theorem at quantum level, obtain the fractional spin of this supersymmetric system, and show that the total angular momentum is the sum of the orbital angular momentum and spin angular momentum of the non-Abelian gauge field. Finally, we obtain the anomalous fractional spin and discover that the fractional spin has the contributions of both the group superscript components and A 0 s (x) charge
Energy Technology Data Exchange (ETDEWEB)
Lenk, Christian Alexander
2009-08-13
Wasserstoff aus der korrosiven Umgebung eindeutig nachweist. Aus diesem Grund wurde speziell fuer diesen Zweck die so genannte Wasserstoffsaege konstruiert und gebaut. Der experimentelle Aufbau nutzt die Methode der thermischen Desorption. Zunaechst werden unter Hochvakuumbedingungen aus der Probe Spaene mit einer Dicke von ca. 20 Mikrometern ausgesaegt. Die Spaene fallen in einen heissen Tiegel in einer UHV-Kammer und es kommt zu einem Ausdampfen des Wasserstoffs aus den Spaenen. Die resultierende Druckerhoehung wird von einem Massenspektrometer aufgenommen, und durch die Zuordnung der zu diesem Signal zugehoerigen Spanposition erhaelt man ein Wasserstoffprofil der Probe. Fuer das korrosive Medium, die NaCl-Loesung, welches die Probe waehrend der Risserzeugung umgibt, wurde Schwerwasser verwendet. Die Verwendung von Schwerwasser macht es moeglich, zwischen dem in der Probe, aus einer technischen Aluminiumlegierung (AA6013), vorhandenen Wasserstoff und dem waehrend der Wechselverformung eindiffundierten Deuterium aus dem Korrosionsmedium zu unterscheiden. Das eindiffundierte Deuterium wird ausschliesslich nur im Probenvolumen im stark plastisch deformierten Bereich um den Ermuedungsriss nachgewiesen. (orig.)
International Nuclear Information System (INIS)
Papp, Z.; Plessas, W.
1996-01-01
We demonstrate the feasibility and efficiency of the Coulomb-Sturmian separable expansion method for generating accurate solutions of the Faddeev equations. Results obtained with this method are reported for several benchmark cases of bosonic and fermionic three-body systems. Correct bound-state results in agreement with the ones established in the literature are achieved for short-range interactions. We outline the formalism for the treatment of three-body Coulomb systems and present a bound-state calculation for a three-boson system interacting via Coulomb plus short-range forces. The corresponding result is in good agreement with the answer from a recent stochastic-variational-method calculation. copyright 1996 The American Physical Society
Coulomb-free and Coulomb-distorted recolliding quantum orbits in photoelectron holography
Maxwell, A. S.; Figueira de Morisson Faria, C.
2018-06-01
We perform a detailed analysis of the different types of orbits in the Coulomb quantum orbit strong-field approximation (CQSFA), ranging from direct to those undergoing hard collisions. We show that some of them exhibit clear counterparts in the standard formulations of the strong-field approximation for direct and rescattered above-threshold ionization, and show that the standard orbit classification commonly used in Coulomb-corrected models is over-simplified. We identify several types of rescattered orbits, such as those responsible for the low-energy structures reported in the literature, and determine the momentum regions in which they occur. We also find formerly overlooked interference patterns caused by backscattered Coulomb-corrected orbits and assess their effect on photoelectron angular distributions. These orbits improve the agreement of photoelectron angular distributions computed with the CQSFA with the outcome of ab initio methods for high energy phtotoelectrons perpendicular to the field polarization axis.
Coulomb blockade induced by magnetic field
International Nuclear Information System (INIS)
Kusmartsev, F.V.
1992-01-01
In this paper, the authors found that a Coulomb blockade can be induced by magnetic field. The authors illustrated this effect on the example of a ring consisting of two and many Josephson junctions. For the ring with two junctions we present an exact solution. The transition into Coulomb blockade state on a ring transforms into a linear array of Josephson junctions, although in latter case the effect of magnetic field disappears. In the state of Coulomb blockade the magnetization may be both diamagnetic and paramagnetic. The Coulomb blockade may also be removed by external magnetic field
International Nuclear Information System (INIS)
Hiratsuka, Y.; Oryu, S.; Gojuki, S.
2011-01-01
Reliability of the screened Coulomb renormalization method, which was proposed in an elegant way by Alt-Sandhas-Zankel-Ziegelmann (ASZZ), is discussed on the basis of 'two-potential theory' for the three-body AGS equations with the Coulomb potential. In order to obtain ASZZ's formula, we define the on-shell Moller function, and calculate it by using the Haeringen criterion, i. e. 'the half-shell Coulomb amplitude is zero'. By these two steps, we can finally obtain the ASZZ formula for a small Coulomb phase shift. Furthermore, the reliability of the Haeringen criterion is thoroughly checked by a numerically rigorous calculation for the Coulomb LS-type equation. We find that the Haeringen criterion can be satisfied only in the higher energy region. We conclude that the ASZZ method can be verified in the case that the on-shell approximation to the Moller function is reasonable, and the Haeringen criterion is reliable. (author)
Global gauge fixing in lattice gauge theories
Energy Technology Data Exchange (ETDEWEB)
Fachin, S.; Parrinello, C. (Physics Department, New York University, 4 Washington Place, New York, New York (USA))
1991-10-15
We propose a covariant, nonperturbative gauge-fixing procedure for lattice gauge theories that avoids the problem of Gribov copies. This is closely related to a recent proposal for a gauge fixing in the continuum that we review. The lattice gauge-fixed model allows both analytical and numerical investigations: on the analytical side, explicit nonperturbative calculations of gauge-dependent quantities can be easily performed in the framework of a generalized strong-coupling expansion, while on the numerical side a stochastic gauge-fixing algorithm is very naturally associated with the scheme. In both applications one can study the gauge dependence of the results, since the model actually provides a smooth'' family of gauge-fixing conditions.
Energy Technology Data Exchange (ETDEWEB)
Lesmeister, F.
2001-07-01
The development of innovative products meeting the customer's needs is getting increasingly complex. The production cost and the time to market must be reduced constantly. Modern methods of preventive quality management like QFD, FMEA and Target Costing offer help but they tend to be complex and costly. The author attempted a modularisation of the methods, with the possibility of linking modules as desired using a commercially available software. [German] Die Entwicklung innovativer, den Kundenbeduerfnissen entsprechender Produkte wird zunehmend komplexer. Die Unternehmen sind gezwungen, die Kosten der Produkterstellung stetig zu reduzieren und den Time-to-Market zu verkuerzen. Moderne Methoden des praeventiven Qualitaetsmanagements wie das QFD, die FMEA und das Target Costing bieten Unterstuetzungsmoeglichkeiten zur Loesung der damit zusammenhaengenden Probleme. Doch ist der Einsatz der oft komplizierten Methoden sehr aufwendig. Gruende hierfuer sind die oft starren Anwendungsschemata, die einem situationsspezifischen Einsatz der Methoden entgegenstehen, und die fehlende Verknuepfung der Methoden. Ergebnis der Arbeit ist eine Modularisierung der Methoden und eine Verknuepfung der einzelnen Methodenmodule. Hierdurch koennen die Methoden an die jeweilige Problemsituation angepasst eingesetzt und dadurch der gesamte Produktentwicklungsprozess durchgaengig unterstuetzt werden. Die Anwendung der Methoden wird mittels einer auf dem Markt erhaeltlichen Software unterstuetzt. (orig.)
Composite gauge bosons of transmuted gauge symmetry
International Nuclear Information System (INIS)
Terazawa, Hidezumi.
1987-10-01
It is shown that effective gauge theories of composite gauge bosons describing the dynamics of composite quarks and leptons can be transmuted from the subcolor gauge theory describing that of subquarks due to the condensation of subquarks and that the equality of effective gauge coupling constants can result as in a grand unified gauge theory. (author)
Gauge-invariant expectation values of the energy of a molecule in an electromagnetic field
International Nuclear Information System (INIS)
Mandal, Anirban; Hunt, Katharine L. C.
2016-01-01
following our partitioning, the expectation values of the molecular Hamiltonian are identical to those obtained directly in the Coulomb gauge. As a corollary of this result, the power absorbed by a molecule from a time-dependent, applied electromagnetic field is equal to the time derivative of the non-adiabatic term in the molecular energy, in any gauge
4. meeting on passive solar energy houses. Proceedings; 4. Passivhaus Tagung. Tagungsband
Energy Technology Data Exchange (ETDEWEB)
Feist, W [ed.; Sariri, V; Nagel, M [comps.; Passivhaus Institut, Darmstadt (Germany)
2000-03-01
This is the report on the 4th Passive Building Conference, which took place at Kassel on March 10/11, 2000. There were eight sections: (a) Planners' workshop; (b) Architecture; (c) Ventilation; (d) Construction practice; (e) Subjective users' comfort and measured results; (f) Practical implementation; (g) economic and ecological assessment; (h) Solar architecture; (i) Heat supply. It was considered particularly favourable that passive solar buildings do not only offer a solution to ecological problems but also a growing market. [German] Der Tagungsband der '4. Passivhaus Tagung', die von 10. bis 11. Maerz 2000 in Kassel stattgefunden hat, beinhalten Beitraege, die in acht Arbeitsgruppen vorgetragen worden: (a) Planer-Werkstatt; (b) Architektur; (c) Lueftungsplanung; (d) Baupraxis; (e) Wohnerfahrung, Messergebnisse; (f) Umsetzung; (g) oekonomische und oekologische Bewertung; (h) Solararchitektur; (i) Waermeversorgung. Es wird vom Herausgeber als besonders erfreulich herausgestellt, dass durch eine erfolgreiche Passivhaus-Entwicklung neben der Loesung der Klimaprobleme zugleich ein neuer Wachstumsmarkt geschaffen werde, der mit einer Mehrung von Wertschoepfung und Wohlstand verbunden ist. (AKF)
Gebremedhin, Daniel H; Weatherford, Charles A
2015-02-01
This is a response to the comment we received on our recent paper "Calculations for the one-dimensional soft Coulomb problem and the hard Coulomb limit." In that paper, we introduced a computational algorithm that is appropriate for solving stiff initial value problems, and which we applied to the one-dimensional time-independent Schrödinger equation with a soft Coulomb potential. We solved for the eigenpairs using a shooting method and hence turned it into an initial value problem. In particular, we examined the behavior of the eigenpairs as the softening parameter approached zero (hard Coulomb limit). The commenters question the existence of the ground state of the hard Coulomb potential, which we inferred by extrapolation of the softening parameter to zero. A key distinction between the commenters' approach and ours is that they consider only the half-line while we considered the entire x axis. Based on mathematical considerations, the commenters consider only a vanishing solution function at the origin, and they question our conclusion that the ground state of the hard Coulomb potential exists. The ground state we inferred resembles a δ(x), and hence it cannot even be addressed based on their argument. For the excited states, there is agreement with the fact that the particle is always excluded from the origin. Our discussion with regard to the symmetry of the excited states is an extrapolation of the soft Coulomb case and is further explained herein.
Coulomb Blockade Plasmonic Switch.
Xiang, Dao; Wu, Jian; Gordon, Reuven
2017-04-12
Tunnel resistance can be modulated with bias via the Coulomb blockade effect, which gives a highly nonlinear response current. Here we investigate the optical response of a metal-insulator-nanoparticle-insulator-metal structure and show switching of a plasmonic gap from insulator to conductor via Coulomb blockade. By introducing a sufficiently large charging energy in the tunnelling gap, the Coulomb blockade allows for a conductor (tunneling) to insulator (capacitor) transition. The tunnelling electrons can be delocalized over the nanocapacitor again when a high energy penalty is added with bias. We demonstrate that this has a huge impact on the plasmonic resonance of a 0.51 nm tunneling gap with ∼70% change in normalized optical loss. Because this structure has a tiny capacitance, there is potential to harness the effect for high-speed switching.
EINE UNTERSUCHUNG UBER DIE NUTZUNG DER WINDENERGIE IN DER WELT UND IN DER TURKEI
Directory of Open Access Journals (Sweden)
Aydoğan ÖZDAMAR
2000-02-01
Full Text Available In dieser Arbeit wurde die Nutzung der in Zukunft bei der Energieversorgung eine wichtige Rolle zuspielende Windenergie allgemein bewertet. Zu dem Zweck wurde zuerst Potential und geschichtliche Entwicklung der Windenergienutzung in der Welt und in der Türkei, Entstehung des Windes und Windmessungen betrachtet. Anschließend wurden Kritiken über die Unstetigkeit der Windenergie, der Deckung des Energiebedarfs eines Hauses vollständig von Windenergie und der Wirtschaftlichkeit des Windstroms behandelt und Antworten mit konkreten Beispielen auf diese Kritiken gegeben.
A new gauge for supersymmetric abelian gauge theories
International Nuclear Information System (INIS)
Smith, A.W.; Barcelos Neto, J.
1984-01-01
A new gauge for supersymmetric abelian gauge theories is presented. It is shown that this new gauge allows us to obtain terms which usually come as radiative corrections to the supersymmetric abelian gauge theories when one uses the Wess-Zumino gauge. (Author) [pt
Comment on "Calculations for the one-dimensional soft Coulomb problem and the hard Coulomb limit".
Carrillo-Bernal, M A; Núñez-Yépez, H N; Salas-Brito, A L; Solis, Didier A
2015-02-01
In the referred paper, the authors use a numerical method for solving ordinary differential equations and a softened Coulomb potential -1/√[x(2)+β(2)] to study the one-dimensional Coulomb problem by approaching the parameter β to zero. We note that even though their numerical findings in the soft potential scenario are correct, their conclusions do not extend to the one-dimensional Coulomb problem (β=0). Their claims regarding the possible existence of an even ground state with energy -∞ with a Dirac-δ eigenfunction and of well-defined parity eigenfunctions in the one-dimensional hydrogen atom are questioned.
Continuum gauge fields from lattice gauge fields
International Nuclear Information System (INIS)
Goeckeler, M.; Kronfeld, A.S.; Schierholz, G.; Wiese, U.J.
1993-01-01
On the lattice some of the salient features of pure gauge theories and of gauge theories with fermions in complex representations of the gauge group seem to be lost. These features can be recovered by considering part of the theory in the continuum. The prerequisite for that is the construction of continuum gauge fields from lattice gauge fields. Such a construction, which is gauge covariant and complies with geometrical constructions of the topological charge on the lattice, is given in this paper. The procedure is explicitly carried out in the U(1) theory in two dimensions, where it leads to simple results. (orig.)
Oschmiansky, Heidi
2007-01-01
"Seit den 1980er Jahren wird der Wandel der Erwerbsformen in der Bundesrepublik Deutschland immer stärker sichtbar. Während die sozial abgesicherte, abhängige und unbefristete Vollzeiterwerbsform - das sog. 'Normalarbeitsverhältnis' - seither leicht an Bedeutung verloren hat, zeigen sich bei den übrigen Erwerbsformen zum Teil hohe Zuwächse und eine zunehmende Differenzierung. Der vorliegende Beitrag untersucht den Wandel der Erwerbsformen zwischen 1985 und 2005 auf Basis von Mikrozensus-Daten...
Classical- and quantum mechanical Coulomb scattering
International Nuclear Information System (INIS)
Gratzl, W.
1987-01-01
Because in textbooks the quantum mechanical Coulomb scattering is either ignored or treated unsatisfactory, the present work attempts to present a physically plausible, mathematically correct but elementary treatment in a way that it can be used in textbooks and lectures on quantum mechanics. Coulomb scattering is derived as a limiting case of a screened Coulomb potential (finite range) within a time dependent quantum scattering theory. The difference in the asymptotic conditions for potentials of finite versus infinite range leads back to the classical Coulomb scattering. In the classical framework many concepts of the quantum theory can be introduced and are useful in an intuitive understanding of the quantum theory. The differences between classical and quantum scattering theory are likewise useful for didactic purposes. (qui)
Zur Sozialgeschichte der Gerechtigkeit in der Neuzeit
Directory of Open Access Journals (Sweden)
Koller Peter
2014-12-01
Full Text Available Der Beitrag verfolgt das Ziel, die Entwicklung der Idee der Gerechtigkeit in der Neuzeit im Kontext des sozialen Wandels zu erhellen. Zu diesem Zweck wird nach einer einleitenden Erörterung des dieser Idee zugrundeliegenden Gerechtigkeitsbegriffs (1 zuerst das Projekt einer vertragstheoretischen Begründung einer gerechten staatlichen Ordnung in der frühen Neuzeit vor dem Hintergrund des Herausbildung des modernen Staates behandelt (2. Im Anschluss werden die theoretischen Leitideen und gesellschaftlichen Triebkräfte des Kampfes um bürgerliche Freiheit und demokratische Teilhabe beleuchtet (3, wovon ausgehend dann die Entstehung der heute vorherrschenden Vorstellung von sozialer Gerechtigkeit einer näheren Betrachtung unterzogen wird (4. Der Beitrag endet mit einigen Bemerkungen über die Gerechtigkeitsprobleme der Gegenwart und die künftigen Herausforderungen im Kampf um Gerechtigkeit (5.
International Nuclear Information System (INIS)
Hoffmann, B.
1984-07-01
In three chapters different physical situations are described which have commonly the Coulomb interaction as driving force. The first two chapters study the Coulomb interactions in connection with the excitation of inner electron shells and the Coulomb excitation of nuclei in first order. In the third part on effect ofthe Coulomb interaction between electronic shell and nucleus is treated in second order (nuclear polarization), and its effect on the isotopic and isomeric shift is studied. (orig./HSI) [de
Energy Technology Data Exchange (ETDEWEB)
Grebe, U.D.; Gebhard, P.; Loehnert, T.; Opacak, I.; Theis, H.G. [Opel Powertrain GmbH, ein Unternehmen von FIAT-GM Powertrain (Germany)
2003-07-01
Tassenstoessel-Ventiltrieb mit mechanischer Spieleinstellung und ein Thermomanagementsystem. Neben der Leistung von 76 kW und einem maximalen Drehmoment von 147 Nm stand die Einfuehrung eines neuen, kraftstoffverbrauchsmindernden Brennverfahrens mit Kanalabschaltung und hoher Abgasrueckfuehrrate im Vordergrund der Entwicklung. Mit Marktstart des neuen Motors im Opel Astra wird der MVEG - Zyklusverbrauch dieses Fahrzeugs um 7% von 7,0 l/100 km auf 6,5 l/100 km gesenkt und nimmt eine Position im Spitzenfeld des Segments ein. Dieses Feld wird ansonsten nur von Ottomotoren mit wesentlich aufwaendigeren Verbrauchsmassnahmen wie beispielsweise der geschichteten Benzindirekteinspritzung besetzt. Die kostenguenstige Loesung des verwendeten Systems verbindet hohen Kundennutzen im Bezug auf Verbrauch und Fahrleistung mit optimierten Herstellungskosten und hoher Langzeitzuverlaessigkeit. Das vorgestellte Konzept mit modularen Grundkomponenten bildet die Plattform fuer die weiterentwickelte Motorengeneration und wird in unterschiedlichen Kombinationen in allen zukuenftigen Versionen der mittleren Vierzylinder-Ottomotorbaureihe zum Einsatz kommen. (orig.)
Coulomb interaction in the supermultiplet basis
International Nuclear Information System (INIS)
Ruzha, Ya.Kh.; Guseva, T.V.; Tamberg, Yu.Ya.; Vanagas, V.V.
1989-01-01
An approximate expression for the matrix elements of the Coulomb interaction operator in the supermultiplet basis has been derived with the account for the orbitally-nonsymmetric terms. From the general expression a simplified formula for the Coulomb interaction energy has been proposed. On the basis of the expression obtained the contribution of the Coulomb interaction to the framework of a strongly restricted dynamic model in the light (4≤A≤40) and heavy (158≤A≤196) nuclei region has been studied. 19 refs.; 4 tabs
Localization of twisted N=(0,2) gauged linear sigma models in two dimensions
Energy Technology Data Exchange (ETDEWEB)
Closset, Cyril [Simons Center for Geometry and Physics, State University of New York, Stony Brook, NY 11794 (United States); Gu, Wei [Department of Physics MC 0435, Virginia Tech, 850 West Campus Drive, Blacksburg, VA 24061 (United States); Jia, Bei [Theory Group, Physics Department, University of Texas, Austin, TX 78612 (United States); Sharpe, Eric [Department of Physics MC 0435, Virginia Tech, 850 West Campus Drive, Blacksburg, VA 24061 (United States)
2016-03-14
We study two-dimensional N=(0,2) supersymmetric gauged linear sigma models (GLSMs) using supersymmetric localization. We consider N=(0,2) theories with an R-symmetry, which can always be defined on curved space by a pseudo-topological twist while preserving one of the two supercharges of flat space. For GLSMs which are deformations of N=(2,2) GLSMs and retain a Coulomb branch, we consider the A/2-twist and compute the genus-zero correlation functions of certain pseudo-chiral operators, which generalize the simplest twisted chiral ring operators away from the N=(2,2) locus. These correlation functions can be written in terms of a certain residue operation on the Coulomb branch, generalizing the Jeffrey-Kirwan residue prescription relevant for the N=(2,2) locus. For abelian GLSMs, we reproduce existing results with new formulas that render the quantum sheaf cohomology relations and other properties manifest. For non-abelian GLSMs, our methods lead to new results. As an example, we briefly discuss the quantum sheaf cohomology of the Grassmannian manifold.
Trinucleon asymptotic normalization constants including Coulomb effects
International Nuclear Information System (INIS)
Friar, J.L.; Gibson, B.F.; Lehman, D.R.; Payne, G.L.
1982-01-01
Exact theoretical expressions for calculating the trinucleon S- and D-wave asymptotic normalization constants, with and without Coulomb effects, are presented. Coordinate-space Faddeev-type equations are used to generate the trinucleon wave functions, and integral relations for the asymptotic norms are derived within this framework. The definition of the asymptotic norms in the presence of the Coulomb interaction is emphasized. Numerical calculations are carried out for the s-wave NN interaction models of Malfliet and Tjon and the tensor force model of Reid. Comparison with previously published results is made. The first estimate of Coulomb effects for the D-wave asymptotic norm is given. All theoretical values are carefully compared with experiment and suggestions are made for improving the experimental situation. We find that Coulomb effects increase the 3 He S-wave asymptotic norm by less than 1% relative to that of 3 H, that Coulomb effects decrease the 3 He D-wave asymptotic norm by approximately 8% relative to that of 3 H, and that the distorted-wave Born approximation D-state parameter, D 2 , is only 1% smaller in magnitude for 3 He than for 3 H due to compensating Coulomb effects
Coulomb-Driven Relativistic Electron Beam Compression.
Lu, Chao; Jiang, Tao; Liu, Shengguang; Wang, Rui; Zhao, Lingrong; Zhu, Pengfei; Xiang, Dao; Zhang, Jie
2018-01-26
Coulomb interaction between charged particles is a well-known phenomenon in many areas of research. In general, the Coulomb repulsion force broadens the pulse width of an electron bunch and limits the temporal resolution of many scientific facilities such as ultrafast electron diffraction and x-ray free-electron lasers. Here we demonstrate a scheme that actually makes use of the Coulomb force to compress a relativistic electron beam. Furthermore, we show that the Coulomb-driven bunch compression process does not introduce additional timing jitter, which is in sharp contrast to the conventional radio-frequency buncher technique. Our work not only leads to enhanced temporal resolution in electron-beam-based ultrafast instruments that may provide new opportunities in probing material systems far from equilibrium, but also opens a promising direction for advanced beam manipulation through self-field interactions.
Coulomb-Driven Relativistic Electron Beam Compression
Lu, Chao; Jiang, Tao; Liu, Shengguang; Wang, Rui; Zhao, Lingrong; Zhu, Pengfei; Xiang, Dao; Zhang, Jie
2018-01-01
Coulomb interaction between charged particles is a well-known phenomenon in many areas of research. In general, the Coulomb repulsion force broadens the pulse width of an electron bunch and limits the temporal resolution of many scientific facilities such as ultrafast electron diffraction and x-ray free-electron lasers. Here we demonstrate a scheme that actually makes use of the Coulomb force to compress a relativistic electron beam. Furthermore, we show that the Coulomb-driven bunch compression process does not introduce additional timing jitter, which is in sharp contrast to the conventional radio-frequency buncher technique. Our work not only leads to enhanced temporal resolution in electron-beam-based ultrafast instruments that may provide new opportunities in probing material systems far from equilibrium, but also opens a promising direction for advanced beam manipulation through self-field interactions.
Zum Begriff der kommunikativen function in der Linguistik
Directory of Open Access Journals (Sweden)
Stojan Bračič
1987-12-01
Full Text Available In diesem Artikel soli der Funktionsbegriff in der Linguistik diskutiert werden, insbesondere der Begr'iff der kotnmunikativen Funktion. Es geht· nur um eine allge meine Behandlung von Charakteristiken des Begriffs kommunikative Funktion. Am Anfang wird eine Rdhe bekannter und doch recht miterschiedlicher Bedeutungsin terpretationert des Funktionsbegriffs in der Linguistik übersichtlich angeführt. Das zweite Unterkapitel versucht es, sich mit verschiedenen Gesichtspunkteri der nach Wilhelm SCHMIDT definierten kommunikativen Funktion auseinanderzusetzen: u. a. mii ihrer Verwurzelung in der funktional korrimunikativen Sprachbesc4reibung, mit dem Unterscheiden von kommunikativen Funktionen auf verschiedenen Ebe nen (kommunikative Funktion des Textes, kommunikative Funktion der Aus drucksmittel, kommunikative Funktion der Sprache bzw. des Sprachsystems, fer nei: zieht es eine hypothetisch annehmbare rezeptive Komponente der kommunikati ven Funktion heran und macht schließlich den Versuch einer Distinktion zwischen direkter (unmittelbarer ud indirekter (mittelbarer Ausprägung einzelner koriimu nikativer Funktionert. Es wird auch auf die Funktion verwiesen, die der Text für den Rezipienten hat. Der Abschluß bringt zusammenfassend die wesentlichen Erkennt nisse dieses Beitrags.
Coulomb drag in the mesoscopic regime
DEFF Research Database (Denmark)
Mortensen, N. Asger; Flensberg, Karsten; Jauho, Antti-Pekka
2002-01-01
We present a theory for Coulomb drug between two mesoscopic systems which expresses the drag in terms of scattering matrices and wave functions. The formalism can be applied to both ballistic and disordered systems and the consequences can be studied either by numerical simulations or analytic...... means such as perturbation theory or random matrix theory. The physics of Coulomb drag in the mesoscopic regime is very different from Coulomb drag between extended electron systems. In the mesoscopic regime we in general find fluctuations of the drag comparable to the mean value. Examples are vanishing...
Coulomb drag in the mesoscopic regime
DEFF Research Database (Denmark)
Mortensen, N.A.; Flensberg, Karsten; Jauho, Antti-Pekka
2002-01-01
We present a theory for Coulomb drag between two mesoscopic systems which expresses the drag in terms of scattering matrices and wave functions. The formalism can be applied to both ballistic and disordered systems and the consequences can be studied either by numerical simulations or analytic...... means such as perturbation theory or random matrix theory. The physics of Coulomb drag in the mesoscopic regime is very different from Coulomb drag between extended electron systems. In the mesoscopic regime we in general find fluctuations of the drag comparable to the mean value. Examples are vanishing...
Der II. Hauptsatz der Wärmelehre
Heintze, Joachim
Wir haben in (4.44) den II. Hauptsatz als empirische Tatsache folgendermaßen formuliert: (i) Wärmeenergie geht von selbst nur von einem wärmeren Körper auf einen kälteren über, niemals in der umgekehrten Richtung. Nun werden wir beweisen, dass sich aus diesem Prinzip folgende äquivalente Formulierungen für den II. Hauptsatz ableiten lassen: (ii) Es ist unmöglich, ein Perpetuum mobile zweiter Art zu bauen, d. h. eine Maschine, die fortlaufend Wärmeenergie vollständig in mechanische Arbeit umsetzen kann. Eine Wärmekraftmaschine, die einen Kreisprozess mit der höchsten Temperatur Tw und der niedrigsten Temperatur Tk durchläuft, hat höchstens den Carnotschen Wirkungsgrad c = (Tw - Tk)/Tw. Wenn in der Maschine nur reversible Prozesse ablaufen, die gesamte Wärmezufuhr bei der Temperatur Tw erfolgt und ausschließlich bei der Temperatur Tw gekühlt wird, ist ihr Wirkungsgrad = C. Es gibt keine Wärmekraftmaschine, die eine bessere Ausnutzung der Wärmeenergie ermöglicht. (iv) In jedem thermodynamischen System existiert die Zustandsgröße Entropie, definiert durch ihr Differential dS = (dQrev)/T . Entropie kann erzeugt, aber nicht vernichtet werden. Bei Zustandsänderungen, die in einem abgeschlossenen System ablaufen, nimmt die Entropie entweder zu (irreversible Prozesse), oder sie bleibt konstant (reversible Prozesse). Im Anschluss an (iii) werden wir zur Definition der thermodynamischen Temperatur und bei der Diskussion von (iv) zu einem tieferen Verständnis der Entropie gelangen. Es zeigt sich, dass die Entropie das eigentliche Bindeglied zwischen Mechanik und Wärmelehre darstellt. Am Ende des Kapitels werden wir einige Anwendungen des II. Hauptsatzes betrachten.
Derivation of the gauge link in light cone gauge
International Nuclear Information System (INIS)
Gao Jianhua
2010-01-01
In light cone gauge, a gauge link at light cone infinity is necessary for transverse momentum-dependent parton distribution to restore the gauge invariance in some specific boundary conditions. We derive such transverse gauge link in a more regular and general method. We find the gauge link at light cone infinity naturally arises from the contribution of the pinched poles: one is from the quark propagator and the other is hidden in the gauge vector field in light cone gauge. Actually, in the amplitude level, we have obtained a more general gauge link over the hypersurface at light cone infinity which is beyond the transverse direction. The difference of such gauge link between semi-inclusive deep inelastic scattering and Drell-Yan processes can also be obtained directly and clearly in our derivation.
Platz der Östrogene in der Primärprävention der Osteoporose
Directory of Open Access Journals (Sweden)
Birkhäuser M
2011-01-01
Full Text Available Die Gabe von Östrogenen allein (EET oder Östrogene + Gestagen (HET führt zu einer signifikanten Senkung des Frakturrisikos. Die Osteoporoseprävention bleibt in der frühen Postmenopause nach Meinung der Schweizerischen (SMG, der Europäischen (EMAS und der Internationalen (IMS Menopausengesellschaften einer der gesicherten Nutzen einer Östrogengabe und somit eine Therapie der ersten Wahl zur Frakturprävention bei Frauen in der Peri- und frühen Postmenopause. Bei schweren klimakterischen Beschwerden sind EET oder HET das unbestritten wirksamste Therapieprinzip (Hauptindikation einer EET/HET. Die gleichzeitig gesicherte Frakturprävention ist bei der Behandlung des klimakterischen Syndroms ein erwünschter günstiger Nebeneffekt. Jede EET/HET muss individualisiert sein und soll nur solange erfolgen, als sie notwendig ist. Bei gegebener Indikation kann die EET oder HET über die üblichen 35 Jahre hinaus fortgesetzt werden. Bei vorzeitiger Menopause (vor dem 40. Altersjahr und früher Menopause (vor dem 45. Altersjahr besteht eine absolute Indikation zum Beginn einer EET/HET. Frauen mit vorzeitiger Ovarialinsuffizienz benötigen meist höhere Dosierungen als solche mit zeitgerechter Menopause. Die EET/HET soll auch aus Gründen der Osteoporoseprävention mindestens bis zum normalen Menopausenalter weitergeführt werden (51 52 Jahre. Bei Beginn einer HET innerhalb von 10 Jahren nach der Menopause oder in einem Alter von bis zu 60 Jahren überwiegt bei gegebener Indikation der Nutzen die Risiken. Dies muss bei der Behandlungswahl bei jüngeren postmenopausalen Frauen mit erhöhtem Osteoporoserisiko wieder vermehrt berücksichtigt werden, vor allem, wenn gleichzeitig klimakterische Beschwerden vorliegen.
Teilchen, Felder, Quanten von der Quantenmechanik zum Standardmodell der Teilchenphysik
Ecker, Gerhard
2017-01-01
Dieses Buch bietet Ihnen eine Einführung in den aktuellen Stand unseres Wissens über die Struktur der Materie. Gerhard Ecker beschreibt verständlich die Entwicklung der modernen Physik vom Beginn des Quantenzeitalters bis zum Standardmodell der Teilchenphysik, der umfassenden Theorie der fundamentalen Wechselwirkungen des Mikrokosmos. Dabei wird der Schwerpunkt auf die wichtigsten Entdeckungen und Entwicklungen, beispielsweise der Quantenfeldtheorie, der Eichtheorien und die Zukunft der Teilchenphysik, gelegt. Besonders hebt der Autor auch das Wechselspiel zwischen Theorie und Experiment hervor, die uns helfen, die tiefsten Rätsel der Natur zu ergründen. Teilchen, Felder, Quanten ist für alle geschrieben, die Freude an der Physik haben. Es bietet Abiturienten und Studierenden der Physik in den ersten Semestern einen Ansporn, die Physik tiefer zu verstehen. Lehrer und andere an der Physik Interessierte werden darin nützliche Einblicke in die Welt der Teilchenphysik finden. Für Studierende in ...
Phases and amplitudes for a modified repulsive Coulomb field
International Nuclear Information System (INIS)
Chidichimo, M.C.; Davison, T.S.
1990-01-01
The asymptotic form of the radial wave function for positive-energy states is calculated for the case of a repulsive Coulomb field. The cases of a pure Coulomb potential and a modified Coulomb potential are considered. Second-order analytic solutions for the amplitudes and phases are obtained when the modifications to the pure Coulombic potential take the form αr -2 +βr -3 +γr -4 , using the Jeffreys or WKB method. For the case of a pure Coulomb field, numerical results obtained from this method were compared with ''exact'' numerical results that were obtained using the analytic properties of the Coulomb wave functions. Tables are presented to show the conditions under which the method is accurate
Intersite Coulomb interaction and Heisenberg exchange
Eder, R; van den Brink, J.; Sawatzky, G.A
1996-01-01
Based on exact diagonalization results for small clusters we discuss the effect of intersite Coulomb repulsion in Mott-Hubbard or charge transfers insulators. Whereas the exchange constant J for direct exchange is enhanced by intersite Coulomb interaction, that for superexchange is suppressed. The
Poisson equation in the Kohn-Sham Coulomb problem
Manby, F. R.; Knowles, Peter James
2001-01-01
We apply the Poisson equation to the quantum mechanical Coulomb problem for many-particle systems. By introducing a suitable basis set, the two-electron Coulomb integrals become simple overlaps. This offers the possibility of very rapid linear-scaling treatment of the Coulomb contribution to Kohn-Sham theory.
Coulomb effects in particle distributions inclusive
International Nuclear Information System (INIS)
Erazmus, B.; Martin, L.; Pluta, J.; Stavinky, A.
1997-01-01
Single pion distributions from central 158 A.GeV/c Pb + Pb collisions measured by the NA44 experiment show the effect of Coulomb interaction with the net charge produced during the reaction. Coulomb effects are analyzed with the help of the microscopic model RQMD and a model including the Coulomb interaction. Different sets of kinematical characteristics of the net charge have been used to reproduce the experimental data and a strong sensitivity to the charge value has been found. This study has evidenced the non-negligible influence of a Coulomb charge, present in the region of the central rapidity in heavy ion collisions on the inclusive distributions of the produced particles. A more thorough analysis of the data obtained from the experiment NA44 is now under way to take into account the hyperon decay that can modify the fraction of different particles, particularly at low transverse momenta
Five-dimensional gauge theory and compactification on a torus
Haghighat, Babak; Vandoren, Stefan
2011-09-01
We study five-dimensional minimally supersymmetric gauge theory compactified on a torus down to three dimensions, and its embedding into string/M-theory using geometric engineering. The moduli space on the Coulomb branch is hyperkähler equipped with a metric with modular transformation properties. We determine the one-loop corrections to the metric and show that they can be interpreted as worldsheet and D1-brane instantons in type IIB string theory. Furthermore, we analyze instanton corrections coming from the solitonic BPS magnetic string wrapped over the torus. In particular, we show how to compute the path-integral for the zero-modes from the partition function of the M5 brane, or, using a 2d/4d correspondence, from the partition function of N=4 SYM theory on a Hirzebruch surface.
Structure and Spectrum of Dust Coulomb Clusters
International Nuclear Information System (INIS)
Cheung, F.M.H.; Ford, C.; Barkby, S.; Samarian, A.A.; Vladimirov, S.V.
2005-01-01
In our study, the dynamics of Coulomb cluster systems were simulated for different number of particles. The spectra of energy states of dust Coulomb clusters corresponding to various packing sequences were obtained. The broadening of the spectrum due to inter-ring twist was discovered. It was found that the inter-ring twist will lead to a change in the energy spectrum of Coulomb cluster. This change was accompanied by a distortion of stable shells such that particles are able to compensate for any additional Coulomb energy (owing to the inter-ring twist) by further reducing their radial distance as much as possible. The overall effect is a change in the shape of the outer-shell from circular to elliptical
Tur\\'an type inequalities for regular Coulomb wave functions
Baricz, Árpád
2015-01-01
Tur\\'an, Mitrinovi\\'c-Adamovi\\'c and Wilker type inequalities are deduced for regular Coulomb wave functions. The proofs are based on a Mittag-Leffler expansion for the regular Coulomb wave function, which may be of independent interest. Moreover, some complete monotonicity results concerning the Coulomb zeta functions and some interlacing properties of the zeros of Coulomb wave functions are given.
Experiments on Coulomb ionization by charged particles
International Nuclear Information System (INIS)
Andersen, J.U.; Laegsgaard, E.; Lund, M.
1978-01-01
Inner-shell ionization by light projectiles, i.e., in very asymmetric collisions, is often denoted 'Coulomb ionization' because it is caused by the Coulomb interaction between the electron and the projectile. Although with little justification, the term is also used to distinquish such processes, in which the projectile Coulomb field is a small perturbation, from ionization in more violent, nearly symmetric ion-atom collisions. A discussion of Coulomb ionization of atomic K shells is given, with emphasis on experimental methods and results. The discussion is not intended as a review of the field but rather as a progress report on the anthor's work on the subject. A more detailed account was recently presented at the ICPEAC meeting in Paris. (Auth.)
Separable expansions for local potentials with Coulomb interactions
International Nuclear Information System (INIS)
Adhikari, S.K.
1976-01-01
If two particles are interacting via a short range potential and a repulsive Coulomb potential the t matrix can be written as a sum of the Coulomb and the ''nuclear'' t matrices. In order to solve the three-nucleon problem with Coulomb interactions usually we need a separable representation of this ''nuclear'' t matrix. A recently proposed method for finding a separable expansion for local potentials is here extended to find a rapidly convergent separable expansion, with analytic form factors, for the ''nuclear'' part of the t matrix of a local potential, in the presence of Coulomb interactions. The method is illustrated for a two-term Malfliet-Tjon potential. In each rank the ''nuclear'' phase shift is close to the corresponding phase shift when the Coulomb interaction is switched off
Coulomb Blockade of Tunnel-Coupled Quantum Dots
National Research Council Canada - National Science Library
Golden, John
1997-01-01
.... Though classical charging models can explain the Coulomb blockade of an isolated dot, they must be modified to explain the Coulomb blockade of dots coupled through the quantum mechanical tunneling of electrons...
Local Momenta and a Three-Body Gauge
Schillaci, Michael Jay
2000-06-01
Here I discuss position-dependent, phlocal momentum which depend upon the logarithmic gradient of a continuum Coulomb pair. These momenta have become increasingly important in the modeling of three-body scattering phenomena, while their precise mathematical and physical nature has remained unexplored. These momenta are analytic at all values of the radial separation, except possibly at zero, and can be used to illustrate why the reigning 3C wavefunction works so well in describing many phlight-atom ion processes. I calculate the contributions for several subsystems, and explain the schillaci/threebody/ momentum.html>asymmetric results achieved by Wiese(L.M. Wiese phet al.), PRL 25, 4982 (1997)., on the breakup of the (H_3^+) ion - a massive three-body system. I propose that the local momentum herein formulated become part of a three-body gauge constraint. When applied, a non-vanishing, position-dependent phase will modulate the resulting transition amplitude. The size of this modulation depends critically upon the system.
Radiative capture versus Coulomb dissociation
International Nuclear Information System (INIS)
Esbensen, H.; Physics
2006-01-01
Measurements of the Coulomb dissociation of 8 B have been used to infer the rate of the inverse radiative proton capture on 7 Be. The analysis is usually based on the assumptions that the two processes are related by detailed balance and described by E1 transitions. However, there are corrections to this relation. The Coulomb form factors for the two processes, for example, are not identical. There are also E2 transitions and higher-order effects in the Coulomb dissociation, and the nuclear induced breakup cannot always be ignored. While adding first-order E2 transitions enhances the decay energy spectrum, the other mechanisms cause a suppression at low relative energies. The net result may accidentally be close to the conventional first-order E1 calculation, but there are differences which cannot be ignored if accuracies of 10% or better are needed
Radiative Capture versus Coulomb Dissociation
International Nuclear Information System (INIS)
Esbensen, Henning
2006-01-01
Measurements of the Coulomb dissociation of 8B have been used to infer the rate of the inverse radiative proton capture on 7Be. The analysis is usually based on the assumptions that the two processes are related by detailed balance and described by E1 transitions. However, there are corrections to this relation. The Coulomb form factors for the two processes, for example, are not identical. There are also E2 transitions and higher-order effects in the Coulomb dissociation, and the nuclear induced breakup cannot always be ignored. While adding first-order E2 transitions enhances the decay energy spectrum, the other mechanisms cause a suppression at low relative energies. The net result may accidentally be close to the conventional first-order E1 calculation, but there are differences which cannot be ignored if accuracies of 10% or better are needed
4. meeting on passive solar energy houses. Proceedings; 4. Passivhaus Tagung. Tagungsband
Energy Technology Data Exchange (ETDEWEB)
Feist, W. [ed.; Sariri, V.; Nagel, M. [comps.] [Passivhaus Institut, Darmstadt (Germany)
2000-03-01
This is the report on the 4th Passive Building Conference, which took place at Kassel on March 10/11, 2000. There were eight sections: (a) Planners' workshop; (b) Architecture; (c) Ventilation; (d) Construction practice; (e) Subjective users' comfort and measured results; (f) Practical implementation; (g) economic and ecological assessment; (h) Solar architecture; (i) Heat supply. It was considered particularly favourable that passive solar buildings do not only offer a solution to ecological problems but also a growing market. [German] Der Tagungsband der '4. Passivhaus Tagung', die von 10. bis 11. Maerz 2000 in Kassel stattgefunden hat, beinhalten Beitraege, die in acht Arbeitsgruppen vorgetragen worden: (a) Planer-Werkstatt; (b) Architektur; (c) Lueftungsplanung; (d) Baupraxis; (e) Wohnerfahrung, Messergebnisse; (f) Umsetzung; (g) oekonomische und oekologische Bewertung; (h) Solararchitektur; (i) Waermeversorgung. Es wird vom Herausgeber als besonders erfreulich herausgestellt, dass durch eine erfolgreiche Passivhaus-Entwicklung neben der Loesung der Klimaprobleme zugleich ein neuer Wachstumsmarkt geschaffen werde, der mit einer Mehrung von Wertschoepfung und Wohlstand verbunden ist. (AKF)
Meilensteine in der Erforschung der kompakten Objekte
Camenzind, Max
Kompakte Objekte besitzen zum einen eine sehr hohe Dichte, und zum anderen sind sie durch die Tatsache charakterisiert, dass keine nuklearen Reaktionen mehr in ihrem Inneren stattfinden können. Aus diesem Grund können sie im Unterschied zu gewöhnlichen Sternen der Gravitation nicht mehr mit dem Druck des thermischen Gases widerstehen. In den Weißen Zwergen bzw. Neutronensternen wird der Gravitation der Quantendruck eines Elektronengases bzw. einer Neutronenflüssigkeit entgegengesetzt. Ein solches Gas besteht aus Elektronen bzw. Neutronen, die auf ihr niedrigstes Energieniveau zusammengepresst wurden. Durch die daraus resultierende hohe Bewegungsenergie der Fermionen wird der sogenannte Quantendruck erzeugt.
Plasma instabilities and turbulence in non-Abelian gauge theories
Energy Technology Data Exchange (ETDEWEB)
Scheffler, Sebastian Herwig Juergen
2010-02-17
Several aspects of the thermalisation process in non-Abelian gauge theories are investigated. Both numerical simulations in the classical statistical approximation and analytical computations in the framework of the two-particle-irreducible effective action are carried out and their results are compared to each other. The physical quantities of central importance are the correlation functions of the gauge field in Coulomb and temporal axial gauge as well as the gauge invariant energy-momentum tensor. Following a general introduction, the theoretical framework of the ensuing investigations is outlined. In doing so, the range of validity of the employed approximation schemes is discussed as well. The first main part of the thesis is concerned with the early stage of the thermalisation process where particular emphasis is on the role of plasma instabilities. These investigations are relevant to the phenomenological understanding of present heavy ion collision experiments. First, an ensemble of initial conditions motivated by the ''colour glass condensate'' is developed which captures characteristic properties of the plasma created in heavy ion collisions. Here, the strong anisotropy and the large occupation numbers of low-momentum degrees of freedom are to be highlighted. Numerical calculations demonstrate the occurrence of two kinds of instabilities. Primary instabilities result from the specific initial conditions. Secondary instabilities are caused by nonlinear fluctuation effects of the preceding primary instabilities. The time scale associated with the instabilities is of order 1 fm/c. It is shown that the plasma instabilities isotropize the initially strongly anisotropic ensemble in the domain of low momenta (
Plasma instabilities and turbulence in non-Abelian gauge theories
International Nuclear Information System (INIS)
Scheffler, Sebastian Herwig Juergen
2010-01-01
Several aspects of the thermalisation process in non-Abelian gauge theories are investigated. Both numerical simulations in the classical statistical approximation and analytical computations in the framework of the two-particle-irreducible effective action are carried out and their results are compared to each other. The physical quantities of central importance are the correlation functions of the gauge field in Coulomb and temporal axial gauge as well as the gauge invariant energy-momentum tensor. Following a general introduction, the theoretical framework of the ensuing investigations is outlined. In doing so, the range of validity of the employed approximation schemes is discussed as well. The first main part of the thesis is concerned with the early stage of the thermalisation process where particular emphasis is on the role of plasma instabilities. These investigations are relevant to the phenomenological understanding of present heavy ion collision experiments. First, an ensemble of initial conditions motivated by the ''colour glass condensate'' is developed which captures characteristic properties of the plasma created in heavy ion collisions. Here, the strong anisotropy and the large occupation numbers of low-momentum degrees of freedom are to be highlighted. Numerical calculations demonstrate the occurrence of two kinds of instabilities. Primary instabilities result from the specific initial conditions. Secondary instabilities are caused by nonlinear fluctuation effects of the preceding primary instabilities. The time scale associated with the instabilities is of order 1 fm/c. It is shown that the plasma instabilities isotropize the initially strongly anisotropic ensemble in the domain of low momenta (< or similar 1 GeV). Essential results can be translated from the gauge group SU(2) to SU(3) by a simple rescaling procedure. Finally, the role of Nielsen-Olesen instabilities in an idealised setup is investigated. In the second part, the quasi
Radionuclides gauges. Gauges designed for permanent installation
International Nuclear Information System (INIS)
1987-06-01
This present norm determines, for radionuclides gauges designed for permanent installation, the characteristics that these gauges should satisfied in their construction and performance to respect the prescriptions. It indicates the testing methods which permit to verify the agreement, gives a classification of gauges and specifies the indications to put on the emitter block [fr
Umsetzung der Unternehmensstrategie mit der Balanced Scorecard
Crespo, Isabel; Bergmann, Lars; Portmann, Stefan; Lacker, Thomas; Lacker, Michael; Fleischmann, Jürgen; Kozó, Hans
Die Balanced Scorecard (BSC) ist ein Ansatz zum strategischen Management, der neben der Ausrichtung des Unternehmens auf finanzielle Zielwerte ebenso großes Gewicht auf so genannte weiche Faktoren legt, die den wirtschaftlichen Erfolg eines Unternehmens erst ermöglichen. Das entscheidende Merkmal der Balanced Scorecard ist dabei, dass sie ein ausgewogenes System strategischer Ziele herstellt, welches das Unternehmen hinsichtlich der vier Perspektiven Finanzen, Kunden, interne Prozesse und Mitarbeiter und Potenziale strategisch ausrichtet (Kaplan u. Norton 1997).
Role amplification of the coulomb interaction in nuclear reactions
Energy Technology Data Exchange (ETDEWEB)
Kumar, Ashok; Soni, S K; Pancholi, S K; Gupta, S L [AN SSSR, Moscow. Radiotekhnicheskij Inst.
1976-10-01
The genarally adopted estimate of coulomb interaction in nuclear reactions based on the comparison of relative energies of real particles participating in the reaction with the coulomb barrier has been shown to provide wrong presentation of the role of coulomb interaction in the reaction mechanism. The relative energy of particles participating in virtual processes forming the reaction mechanism and its relation to the coulomb barrier turn out to be tens of per cent less than for the particles in an inlet channel. This is the main reason of increasing the role of coulomb interaction in the reaction mechanism. This increase is particularly significant for nuclei with large charges, in particular, in heavy ion reaction.
Coulomb Effects in Few-Body Reactions
Directory of Open Access Journals (Sweden)
Deltuva A.
2010-04-01
Full Text Available The method of screening and renormalization is used to include the Coulomb interaction between the charged particles in the momentum-space description of three- and four-body nuclear reactions. The necessity for the renormalization of the scattering amplitudes and the reliability of the method is demonstrated. The Coulomb effect on observables is discussed.
Energy Technology Data Exchange (ETDEWEB)
Loeser, C; Zehnsdorf, A; Hoffmann, P; Seidel, H; Schmerold, R
2002-07-01
Sedimente mit Sauerstoff in Kontakt, gehen die Schwermetalle durch mikrobielle Oxidations- und Versauerungsprozesse teilweise in Loesung. Dieses natuerliche Bioleaching, welches unkontrolliert ein Gefahrenpotential fuer die Umwelt darstellt, soll durch Aktivierung der autochthonen schwefeloxidierenden Bakterien (z.B. Thiobacilli) beschleunigt und zur Reinigung der Sedimente genutzt werden. Ziel ist es, ein naturnahes Verfahren zur Sedimentdekontamination unter Nutzung des natuerlichen biologischen Solubilisierungspotentials bereitzustellen. Die gereinigten Sedimente sollen in den Stoffkreislauf als Bodensubstrat zurueckgefuehrt werden. Die Verfahrensentwicklung erfolgte am Beispiel von hochbelasteten Sedimenten der Weissen Elster aus dem Suedraum Leipzig. Aus oekonomischen Gruenden soll das Bioleaching der Schwermetalle durch Festbettlaugung nach dem Perkolationsprinzip erfolgen. Das Verfahren erfordert mehrere Prozessstufen. Der Schwerpunkt der Untersuchungen im Labor- und Technikumsmassstab lag auf der Erarbeitung und technischen Umsetzung von Massnahmen zur Beschleunigung der Metallsolubilisierung. (orig.)
Selfconsistent theory of Coulomb mixing in nuclei
International Nuclear Information System (INIS)
Pyatov, N.I.
1978-01-01
The theory of isobaric states is considered according to the Coulomb mixing in nuclei. For a given form of the isovestor potential the separable residual interactions are constructed by means of the isotopic invariance principle. The strength parameter of the force is found from a selfconsistency condition. The charge dependent force is represented by the Coulomb effective potential. The theory of the isobaric states is developed using the random phase approximation. The Coulomb mixing effects in the ground and isobaric 0 + states of even-mass nuclei are investigated
The eikonal phase of supersymmetric Coulomb partners
Lassaut, M; Lombard, R J
1998-01-01
We investigate the eikonal phase and its systematic corrections for the two supersymmetric Coulomb partners V sub 1 and V sub 2 derived by Amado. Apart from a constant shift of -pi for V sub 1 and -2 pi for V sub 2 , the eikonal phase decay to the eikonal phase of the Coulomb potential as 1/kb. For the potential V sub 2 , which is phase equivalent to the Coulomb potential, this result is only valid at b approx =0 and asymptotically; in the intermediate range, it constitutes a lower limit. (author)
Fourier acceleration in lattice gauge theories. I. Landau gauge fixing
International Nuclear Information System (INIS)
Davies, C.T.H.; Batrouni, G.G.; Katz, G.R.; Kronfeld, A.S.; Lepage, G.P.; Wilson, K.G.; Rossi, P.; Svetitsky, B.
1988-01-01
Fourier acceleration is a useful technique which can be applied to many different numerical algorithms in order to alleviate the problem of critical slowing down. Here we describe its application to an optimization problem in the simulation of lattice gauge theories, that of gauge fixing a configuration of link fields to the Landau gauge (partial/sub μ/A/sup μ/ = 0). We find that a steepest-descents method of gauge fixing link fields at β = 5.8 on an 8 4 lattice can be made 5 times faster using Fourier acceleration. This factor will grow as the volume of the lattice is increased. We also discuss other gauges that are useful to lattice-gauge-theory simulations, among them one that is a combination of the axial and Landau gauges. This seems to be the optimal gauge to impose for the Fourier acceleration of two other important algorithms, the inversion of the fermion matrix and the updating of gauge field configurations
Gauge-fixing parameter dependence of two-point gauge-variant correlation functions
International Nuclear Information System (INIS)
Zhai, C.
1996-01-01
The gauge-fixing parameter ξ dependence of two-point gauge-variant correlation functions is studied for QED and QCD. We show that, in three Euclidean dimensions, or for four-dimensional thermal gauge theories, the usual procedure of getting a general covariant gauge-fixing term by averaging over a class of covariant gauge-fixing conditions leads to a nontrivial gauge-fixing parameter dependence in gauge-variant two-point correlation functions (e.g., fermion propagators). This nontrivial gauge-fixing parameter dependence modifies the large-distance behavior of the two-point correlation functions by introducing additional exponentially decaying factors. These factors are the origin of the gauge dependence encountered in some perturbative evaluations of the damping rates and the static chromoelectric screening length in a general covariant gauge. To avoid this modification of the long-distance behavior introduced by performing the average over a class of covariant gauge-fixing conditions, one can either choose a vanishing gauge-fixing parameter or apply an unphysical infrared cutoff. copyright 1996 The American Physical Society
2010-10-01
... § 52.01-110 Water-level indicators, water columns, gauge-glass connections, gauge cocks, and pressure... 46 Shipping 2 2010-10-01 2010-10-01 false Water-level indicators, water columns, gauge-glass connections, gauge cocks, and pressure gauges (modifies PG-60). 52.01-110 Section 52.01-110 Shipping COAST...
Fay, Temple H.
2012-01-01
Viscous damping is commonly discussed in beginning differential equations and physics texts but dry friction or Coulomb friction is not despite dry friction being encountered in many physical applications. One reason for avoiding this topic is that the equations involve a jump discontinuity in the damping term. In this article, we adopt an energy…
Der mediale Habitus in der frühen Kindheit
Directory of Open Access Journals (Sweden)
Christian Swertz
2014-12-01
Full Text Available Die empirische Untersuchung der Medienkultur 3- bis 6-jähriger Kindergartenkinder steht im Mittelpunkt des Beitrags. Zum Verständnis der Medienkultur wird der Begriff des medialen Habitus verwendet. Die Ergebnisse zeigen, dass der Begriff des me-dialen Habitus geeignet ist, um die Medienkultur 3- bis 6-Jähriger zu verstehen, und dass der Ausdruck des medialen Habitus mit einem triangulativen qualitativen Design erfasst werden kann.
Eikonal representation of N-body Coulomb scattering amplitudes
International Nuclear Information System (INIS)
Fried, H.M.; Kang, K.; McKellar, B.H.J.
1983-01-01
A new technique for the construction of N-body Coulomb scattering amplitudes is proposed, suggested by the simplest case of N = 2: Calculate the scattering amplitude in eikonal approximation, discard the infinite phase factors which appear upon taking the limit of a Coulomb potential, and treat the remainder as an amplitude whose absolute value squared produces the exact, Coulomb differential cross section. The method easily generalizes to the N-body Coulomb problem for elastic scattering, and for inelastic rearrangement scattering of Coulomb bound states. We give explicit results for N = 3 and 4; in the N = 3 case we extract amplitudes for the processes (12)+3->1+2+3 (breakup), (12)+3->1+(23) (rearrangement), and (12)+3→(12)'+3 (inelastic scattering) as residues at the appropriate poles in the free-free amplitude. The method produces scattering amplitudes f/sub N/ given in terms of explicit quadratures over (N-2) 2 distinct integrands
Bound and resonant states in Coulomb-like potentials
International Nuclear Information System (INIS)
Papp, Z.
1985-12-01
The potential separable expansion method was generalized for calculating bound and resonant states in Coulomb-like potentials. The complete set of Coulomb-Sturmian functions was taken as the basis to expand the short-range potential. On this basis the matrix elements of the Coulomb-Green functions were given in closed form as functions of the (complex) energy. The feasibility of the method is demonstrated by a numerical example. (author)
The Coulomb potential in quantum mechanics and related topics
International Nuclear Information System (INIS)
Haeringen, H. van.
1978-01-01
This dissertation consists of an analytic study of the Coulomb interaction in nonrelativistic quantum mechanics and some related topics. The author investigates in a number of self-contained articles various interesting and important properties of the Coulomb potential. Some of these properties are shared by other potentials which also play a role in quantum mechanics. For such related interactions a comparative study is made. The principal difficulties in the description of proton-deuteron scattering and break-up reactions, due to the Coulomb interaction, are studied by working out a simple model. The bound states are studied for the Coulomb plus Yamaguchi potential, for the symmetric shifted Coulomb potential, and for local potentials with an inverse-distance-squared asymptotic behaviour. (Auth.)
On rate-state and Coulomb failure models
Gomberg, J.; Beeler, N.; Blanpied, M.
2000-01-01
We examine the predictions of Coulomb failure stress and rate-state frictional models. We study the change in failure time (clock advance) Δt due to stress step perturbations (i.e., coseismic static stress increases) added to "background" stressing at a constant rate (i.e., tectonic loading) at time t0. The predictability of Δt implies a predictable change in seismicity rate r(t)/r0, testable using earthquake catalogs, where r0 is the constant rate resulting from tectonic stressing. Models of r(t)/r0, consistent with general properties of aftershock sequences, must predict an Omori law seismicity decay rate, a sequence duration that is less than a few percent of the mainshock cycle time and a return directly to the background rate. A Coulomb model requires that a fault remains locked during loading, that failure occur instantaneously, and that Δt is independent of t0. These characteristics imply an instantaneous infinite seismicity rate increase of zero duration. Numerical calculations of r(t)/r0 for different state evolution laws show that aftershocks occur on faults extremely close to failure at the mainshock origin time, that these faults must be "Coulomb-like," and that the slip evolution law can be precluded. Real aftershock population characteristics also may constrain rate-state constitutive parameters; a may be lower than laboratory values, the stiffness may be high, and/or normal stress may be lower than lithostatic. We also compare Coulomb and rate-state models theoretically. Rate-state model fault behavior becomes more Coulomb-like as constitutive parameter a decreases relative to parameter b. This is because the slip initially decelerates, representing an initial healing of fault contacts. The deceleration is more pronounced for smaller a, more closely simulating a locked fault. Even when the rate-state Δt has Coulomb characteristics, its magnitude may differ by some constant dependent on b. In this case, a rate-state model behaves like a modified
Kulmar, Tarmo, 1950-
2003-01-01
Ettekanne sümpoosionilt: Gemeinsames Symposium der Evangelisch-Theologischen Fakultät der Universität Tartu, der Estnischen Studiengesellschaft für Morgenlandkunde und der Deutschen Religionsgeschichtlichen Studiengesellschaft. Tartu, 2001
International Nuclear Information System (INIS)
Sowerby, B.D.
1982-01-01
Techniques employed in nuclear gauges for the measurement of level, thickness, density and moisture are described. The gauges include both transmission and backscatter gauges and utilize alpha particles, beta particles, neutrons or gamma radiation
Energy Technology Data Exchange (ETDEWEB)
Radgen, P.; Jochem, E. [eds.
1999-10-26
The forum intended to provide written information for experts and to develop model projects for selected fields of industry in Baden-Wuerttemberg. However, these two instruments can only be part of an innovation initiative headed by the Land government in cooperation with the Baden-Wuerttemberg industry and science. [German] Der Schwerpunkt des Forums 'Strom effizient nutzen' konzentrierte sich auf die Erarbeitung von schriftlichen Informationen fuer den Fachmann sowie auf die Entwicklung einiger Modellvorhaben fuer einige ausgewaehlte Branchen Baden-Wuerttembergs. Diese beiden Instrumente koennen aber nur Teil einer Innovationsinitiative sein, die Regierung, Wirtschaft und Wissenschaft entwickeln muessten, wollte man einen sichtbaren Erfolg bei der Loesung des o.g. Zielkonfliktes verbuchen. Eine solche Initiative zu konzipieren und zu entfesseln, die der baden-wuerttembergischen Wirtschaft manch positive Impulse braechte, waere machbar; wie die Modellvorhaben dieses Projektes in ueberzeugender Weise belegen, gibt es hinreichend rentable Moeglichkeiten. (orig.)
Review: Gerd Jüttemann (Hrsg. (2013. Die Entwicklung der Psyche in der Geschichte der Menschheit
Directory of Open Access Journals (Sweden)
Uwe Krebs
2015-03-01
Full Text Available Der Vorbereitungsband für die Reihe "Die Psychogenese der Menschheit" – ein Sammelband aus 32 Beiträgen, betitelt "Die Entwicklung der Psyche in der Geschichte der Menschheit" und 2013 herausgegeben von Gerd JÜTTEMANN – wird in dieser Besprechung in mehreren Schritten vorgestellt und bewertet. Zunächst wird kontextuell argumentiert, dass die bewährte, empirisch-experimentelle Methodologie der Psychologie zur Vernachlässigung weiterer Erkenntnisverfahren führte, die bei Themen wie dem hier zu besprechenden Werk allein verbleiben und die kurz angesprochen werden. Sodann wird das Werk im Überblick knapp dargestellt und die außergewöhnliche Heterogenität in Inhalten und Methoden betont. Die Besprechung einzelner Beiträge, die nach dem Gesichtspunkt großer Unterschiedlichkeit ausgewählt wurden, schließt sich an. Die abschließende Gesamtbewertung betont den lückenhaften Forschungsstand, die Notwendigkeit der allein verbleibenden qualitativen Methodik mit ihren verschiedenen Möglichkeiten und nennt Desiderata künftigen Vorgehens für diesen thematisch und methodisch interessanten Auftakt-Band, der insbesondere durch Dichte und Verschiedenheit der Beiträge beeindruckt. URN: http://nbn-resolving.de/urn:nbn:de:0114-fqs1502219
Sabine Wallig; Judith Dögl; Isabella Seidl; Marlene Giesa
2015-01-01
Die Universitätsbibliothek der Medizinischen Universität Wien verfügt über ein wertvolles kulturhistorisches Erbe, das die Geschichte der „Wiener Medizinischen Schule“ repräsentiert. Einen Teil der in der Zweigbibliothek für Geschichte der Medizin beherbergten historischen Literatur bilden die medizinhistorischen Separatasammlungen. Diese Unikate stellen einen unschätzbaren Mehrwert als Quellenmaterial für medizinhistorische und biografische Forschungen dar. Bei den etwa 140.000 Einzele...
„Sprache, du heilige“: Sprachreflexionen in der deutschen Dichtung der Bukowina
Directory of Open Access Journals (Sweden)
Petro Rychlo
2017-12-01
Full Text Available Der Aufsatz befasst sich mit der historischen und kulturellen Rolle der deutschen Sprache in der Bukowina, wo sie zwischen 1875 und 1918 den Status einer offiziellen Staats- und Umgangssprache hatte und sogar nach dem Zerfall der Habsburgermonarchie noch eine Zeitlang auf verschiedenen Ebenen funktionierte. Das verursachte in der Bukowina und besonders in ihrer Hauptstadt Czernowitz die Herausbildung einer deutschsprachigen Literatur, deren Anfänge in die Mitte des 19. Jahrhundert fallen. Zuerst nur als „Heimatliteratur“ begriffen, entwickelte sie sich bald, vor allem auf dem Gebiet der lyrischen Dichtung, zu einem beachtlichen literarischen Phänomen, das in der Zwischenkriegszeit im Werk solcher Dichter wie Alfred Margul-Sperber, Rose Ausländer, David Goldfeld, Alfred Kittner, Moses Rosenkranz, Immanuel Weißglas, Paul Celan, Alfred Gong, Selma Meerbaum-Eisinger ihre höchste Blüte erlebte. Infolge der fortschreitenden Romanisierung des Landes und der Bedrohung des Sprachverlusts greifen um diese Zeit viele Czernowitzer deutschjüdische Dichter öfters zur Sprachproblematik, indem sie sie in ihren Gedichten im tragischen Sinne thematisieren. Nach dem Holocaust und der Emigration aus der Bukowina verwandelt sich die Muttersprache für verbannte Dichter in ein Synonym der Heimat („Mutterland Wort“. Der Artikel analysiert Sprachreflexionen der Czernowitzer Autoren als Strategie des kulturellen und existenziellen Überlebens.
Coulomb corrections in the low-energy scattering
International Nuclear Information System (INIS)
Mur, V.D.; Popov, V.S.
1985-01-01
Renormalization of the coefficients of the ''effective range expansion'' is considered for the short-range Coulomb problem. The exactly solvable model of the Coulomb plus short range potential is considered. Exact solutions are compared with approximations frequently used in the theory of hadronic atoms
Some studies in scatering by Coulomb modified nuclear potentials
International Nuclear Information System (INIS)
Laha, U.
1988-01-01
Recently, there has been a surge of interest in theoretical questions concerning the Coulomb nuclear problems with the main emphasis on their off-shell behaviour. Earlier approaches to the problem made use of a version of the two-potential formula as used by Bajzer. A slightly different point of view is presented here. An expression for the interacting Green's function for motion in the Coulomb plus Graz potential is constructed and used to obtain the half-off-shell T matrix in the ''maximal reduced form''. Similar results were also derived for the off-shell Jost functions. It is explicitly demonstrated that Coulomb and Coulomb-like potentials the half-off-shell T matrix can be expressed in terms of on-and off-shell Jost functions in the same way as one does for a purely short range interaction. In presenting the results for T matrix and other related quantities, the Coulomb effect is included rigorously. Results clearly delineate the branch point singularities originating from the long range nature of the Coulomb interaction and thus provide a better understanding of the off-shell two-body Coulomb-like T matrices. It is hoped that these results will form an adequate starting point for rigorous calculations on few-body systems with charges. (author). 16 refs
Intergrain Coupling in Dusty-Plasma Coulomb Crystals
International Nuclear Information System (INIS)
Mohideen, U.; Smith, M.A.; Rahman, H.U.; Rosenberg, M.; Mendis, D.A.
1998-01-01
We have studied the lattice structure of dusty-plasma Coulomb crystals formed in rectangular conductive grooves as a function of plasma temperature and density. The crystal appears to be made of mutually repulsive columns of grains confined by the walls of the groove. The columns are oriented along the direction of the electrode sheath electric field. A simple phenomenological model wherein the intergrain spacing results from an attractive electric-field-induced dipole-dipole force balanced by a repulsive monopole Coulomb force is consistent with observed features of the Coulomb crystal. copyright 1998 The American Physical Society
International Nuclear Information System (INIS)
Power, B.D.; Priestland, C.R.D.
1978-01-01
This invention relates to vacuum gauges, particularly of the type known as Penning gauges, which are cold cathode ionisation gauges, in which a magnetic field is used to lengthen the electron path and thereby increase the number of ions produced. (author)
Approximate Coulomb effects in the three-body scattering problem
International Nuclear Information System (INIS)
Haftel, M.I.; Zankel, H.
1981-01-01
From the momentum space Faddeev equations we derive approximate expressions which describe the Coulomb-nuclear interference in the three-body elastic scattering, rearrangement, and breakup problems and apply the formalism to p-d elastic scattering. The approximations treat the Coulomb interference as mainly a two-body effect, but we allow for the charge distribution of the deuteron in the p-d calculations. Real and imaginary parts of the Coulomb correction to the elastic scattering phase shifts are described in terms of on-shell quantities only. In the case of pure Coulomb breakup we recover the distorted-wave Born approximation result. Comparing the derived approximation with the full Faddeev p-d elastic scattering calculation, which includes the Coulomb force, we obtain good qualitative agreement in S and P waves, but disagreement in repulsive higher partial waves. The on-shell approximation investigated is found to be superior to other current approximations. The calculated differential cross sections at 10 MeV raise the question of whether there is a significant Coulomb-nuclear interference at backward angles
Coulomb states in atoms and solids
International Nuclear Information System (INIS)
Ortalano, D.M.
1988-05-01
In this dissertation, an empirical quantum defect approach to describe the valence excitons of the rare gas solids is developed. These Coulomb states are of s-symmetry and form a hydrogen-like series which converges to the bottom of the lowest conduction band. A non-zero quantum defect is found for all of the excitons of neon, argon and xenon. For these systems, then, there exists, in addition to the screened Coulombic component, a non-Coulombic component to the total exciton binding energy. The Wannier formalism is, therefore, inappropriate for the excitons of Ne, Ar and Xe. From the sign of the quantum defect, the non-Coulombic potential is repulsive for Ne and Ar, attractive for Xe, and nearly zero for Kr. This is opposite to that for the Rydberg states of the corresponding rare gas atoms, where the non-Coulombic potential between the electron and the cation is attractive for all of the atoms. The excitons then, are not simply perturbed Rydberg states of the corresponding rare gas atoms (i.e., the excitons do not possess atomic parentage). Interatomic term value/band gap energy correlations and reduced term value/reduced band gap correlations were performed. These correlations were exploited to provide further evidence against both the Wannier formalism and the atomic parentage view point. From these correlations, it was also discovered that the non-Coulombic potential varies smoothly across the valence isoelectronic series of solids, and that it becomes more attractive (or less repulsive) in going from neon to xenon. In order to address the atomic parentage controversy, it was necessary to compare the excitons to the low-n Rydberg states of the rare gas atoms. A review of the quantum defect description of the atomic Rydberg states is, therefore, presented. Also, Rydberg term value/ionization energy correlations are discussed and compared with the analogous exciton correlations. 7 refs., 10 figs., 5 tabs
Coulomb explosion of “hot spot”
Energy Technology Data Exchange (ETDEWEB)
Oreshkin, V. I., E-mail: oreshkin@ovpe.hcei.tsc.ru [Institute of High Current Electrons, SB, RAS, Tomsk (Russian Federation); Tomsk Polytechnic University, Tomsk (Russian Federation); Oreshkin, E. V. [P. N. Lebedev Physical Institute, RAS, Moscow (Russian Federation); Chaikovsky, S. A. [Institute of High Current Electrons, SB, RAS, Tomsk (Russian Federation); P. N. Lebedev Physical Institute, RAS, Moscow (Russian Federation); Institute of Electrophysics, UD, RAS, Ekaterinburg (Russian Federation); Artyomov, A. P. [Institute of High Current Electrons, SB, RAS, Tomsk (Russian Federation)
2016-09-15
The study presented in this paper has shown that the generation of hard x rays and high-energy ions, which are detected in pinch implosion experiments, may be associated with the Coulomb explosion of the hot spot that is formed due to the outflow of the material from the pinch cross point. During the process of material outflow, the temperature of the hot spot plasma increases, and conditions arise for the plasma electrons to become continuously accelerated. The runaway of electrons from the hot spot region results in the buildup of positive space charge in this region followed by a Coulomb explosion. The conditions for the hot spot plasma electrons to become continuously accelerated have been revealed, and the estimates have been obtained for the kinetic energy of the ions generated by the Coulomb explosion.
Coulomb explosion of “hot spot”
International Nuclear Information System (INIS)
Oreshkin, V. I.; Oreshkin, E. V.; Chaikovsky, S. A.; Artyomov, A. P.
2016-01-01
The study presented in this paper has shown that the generation of hard x rays and high-energy ions, which are detected in pinch implosion experiments, may be associated with the Coulomb explosion of the hot spot that is formed due to the outflow of the material from the pinch cross point. During the process of material outflow, the temperature of the hot spot plasma increases, and conditions arise for the plasma electrons to become continuously accelerated. The runaway of electrons from the hot spot region results in the buildup of positive space charge in this region followed by a Coulomb explosion. The conditions for the hot spot plasma electrons to become continuously accelerated have been revealed, and the estimates have been obtained for the kinetic energy of the ions generated by the Coulomb explosion.
Die Rolle der Finite-Elemente-Berechnung in der Produktentwicklung
Esteban, Ignacio
Der Preisdruck wird in allen Industriebranchen immer größer. Aufgrund der Qualitätsstandards gewinnt der Entwicklungsprozess immer mehr an Bedeutung, so dass die Produktkosten durch diese Phase erheblich beeinflusst werden. Die Anwendung computergestützter Konstruktion und Berechnung hat sich als effektives Entwicklungswerkzeug erwiesen, um kürzere Entwicklungszeiten und eine höhere Qualität zu erreichen. Dadurch tragen diese virtuellen Werkzeuge zu niedrigeren Produktkosten bei. Dieser Artikel orientiert sich am Potential der Finite-Elemente (FE)-Berechnung im Entwicklungsprozess. Eine der neuesten Anwendungsmöglichkeiten der FE-Simulation wird am Beispiel einer Werkzeugmaschine präsentiert. In diesem Beispiel wird die Maschinensteuerung in das FE-Modell implementiert, und ein Beschleunigungsvorgang wird simuliert.
Directory of Open Access Journals (Sweden)
Storr, Stefan
2017-12-01
Full Text Available Der vorliegende Kommentar bezieht sich auf den Beitrag „Der digitalisierte Forscher“ von Thomas Kröll (ALJ 2/2017, 71. Ausgehend von der Beschreibung der gegenwärtigen Gesellschaft als Wissensgesellschaft werden drei Aspekte angeführt, die die Wissenschaft als System heute kennzeichnen und künftig weitere Bedeutung haben werden: die Gewinnung und Weitergabe von Forschungsdaten, die Bewertung von wissenschaftlichen Leistungen und die Funktion von Universitäten. Der Kommentar schließt mit der Aufforderung, das Grundrecht der Wissenschaftsfreiheit als institutionelle Garantie fortzuentwickeln.
Scattering and stopping of swift diatomic molecules under Coulomb explosion
International Nuclear Information System (INIS)
Sigmund, P.
1992-01-01
The scattering and stopping of the fragments of a fast diatomic molecule under Coulomb explosion has been analysed theoretically. The central assumption in the scheme is the dominance of Coulomb explosion, while electronic stopping (including wake forces) and elastic scattering are treated as perturbations. Charge exchange has been neglected. Coulomb images of penetration phenomena are heavily distorted. For small penetrated layer thicknesses, images appear contracted in the direction of the molecular axis, and expanded perpendicular to it. This distortion is described quantitatively by a linear transformation. General expressions have been derived for the effect of continuous and stochastic forces on the distribution of fragment velocities from Coulomb explosion (the ''ring pattern''). Moreover, relations have been found that allow to scale velocity distributions valid in the absence of Coulomb explosion into distributions allowing for Coulomb explosion. Applications concern the shift in ring pattern due to electronic stopping, the lateral broadening due to multiple scattering, and the effect of zero-point motion on the Coulomb image of a molecule. (orig.)
Scattering and stopping of swift diatomic molecules under Coulomb explosion
International Nuclear Information System (INIS)
Sigmund, P.
1991-01-01
The scattering and stopping of the fragments of a fast diatomic molecule under Coulomb explosion has been analyzed theoretically. The central assumption in the scheme is the dominance of Coulomb explosion, while electronic stopping (including wake forces) and elastic scattering are treated as perturbations. Charge exchange has been neglected. Coulomb images of penetration phenomena are heavily distorted. For small penetrated layer thicknesses, images appear contracted in the direction of the molecular axis, and expanded perpendicular to it. This distortion is described quantitatively by a linear transformation. General expressions have been derived for the effect of continuous and stochastic forces on the distribution of fragment velocities from Coulomb explosion (the ''ring pattern''). Moreover, relations have been found that allow to scale velocity distributions valid in the absence of Coulomb explosion into distributions allowing for Coulomb explosion. Applications concern the shift in ring pattern due to electronic stopping, the lateral broadening due to multiple scattering and the effect of zero-point motion on the Coulomb image of a molecule. 14 refs., 5 figs
Subcycle dynamics of Coulomb asymmetry in strong elliptical laser fields.
Li, Min; Liu, Yunquan; Liu, Hong; Ning, Qicheng; Fu, Libin; Liu, Jie; Deng, Yongkai; Wu, Chengyin; Peng, Liang-You; Peng, Liangyou; Gong, Qihuang
2013-07-12
We measure photoelectron angular distributions of noble gases in intense elliptically polarized laser fields, which indicate strong structure-dependent Coulomb asymmetry. Using a dedicated semiclassical model, we have disentangled the contribution of direct ionization and multiple forward scattering on Coulomb asymmetry in elliptical laser fields. Our theory quantifies the roles of the ionic potential and initial transverse momentum on Coulomb asymmetry, proving that the small lobes of asymmetry are induced by direct ionization and the strong asymmetry is induced by multiple forward scattering in the ionic potential. Both processes are distorted by the Coulomb force acting on the electrons after tunneling. Lowering the ionization potential, the relative contribution of direct ionization on Coulomb asymmetry substantially decreases and Coulomb focusing on multiple rescattering is more important. We do not observe evident initial longitudinal momentum spread at the tunnel exit according to our simulation.
International Nuclear Information System (INIS)
Kenyon, I.R.
1986-01-01
Modern theories of the interactions between fundamental particles are all gauge theories. In the case of gravitation, application of this principle to space-time leads to Einstein's theory of general relativity. All the other interactions involve the application of the gauge principle to internal spaces. Electromagnetism serves to introduce the idea of a gauge field, in this case the electromagnetic field. The next example, the strong force, shows unique features at long and short range which have their origin in the self-coupling of the gauge fields. Finally the unification of the description of the superficially dissimilar electromagnetic and weak nuclear forces completes the picture of successes of the gauge principle. (author)
Correlated Coulomb drag in capacitively coupled quantum-dot structures
DEFF Research Database (Denmark)
Kaasbjerg, Kristen; Jauho, Antti-Pekka
2016-01-01
We study theoretically Coulomb drag in capacitively coupled quantum dots (CQDs) -- a biasdriven dot coupled to an unbiased dot where transport is due to Coulomb mediated energy transfer drag. To this end, we introduce a master-equation approach which accounts for higher-order tunneling (cotunneling......) processes as well as energy-dependent lead couplings, and identify a mesoscopic Coulomb drag mechanism driven by nonlocal multi-electron cotunneling processes. Our theory establishes the conditions for a nonzero drag as well as the direction of the drag current in terms of microscopic system parameters...... on Coulomb drag in CQD systems....
Coulomb gap triptych in a periodic array of metal nanocrystals.
Chen, Tianran; Skinner, Brian; Shklovskii, B I
2012-09-21
The Coulomb gap in the single-particle density of states (DOS) is a universal consequence of electron-electron interaction in disordered systems with localized electron states. Here we show that in arrays of monodisperse metallic nanocrystals, there is not one but three identical adjacent Coulomb gaps, which together form a structure that we call a "Coulomb gap triptych." We calculate the DOS and the conductivity in two- and three-dimensional arrays using a computer simulation. Unlike in the conventional Coulomb glass models, in nanocrystal arrays the DOS has a fixed width in the limit of large disorder. The Coulomb gap triptych can be studied via tunneling experiments.
International Nuclear Information System (INIS)
Brandao, S.B.
1987-01-01
The level structure of 189 Os has been studied by Coulomb excitation using 35 Cl, 28 Si, 16 O beams. GOSIA, a code written to analyze multiple Coulomb excitation, was used to obtain the reduced probabilities of transition B(E2). The results for interband and intraband turned out possible the classification of the states following Nilsson levels. Gamma-rays originating from deexcitation of 216.7 and 219.4 keV have been separated and the reduced probability of transition has been measured. (A.C.A.S.) [pt
The string unification of gauge couplings and gauge kinetic mixings
International Nuclear Information System (INIS)
Hattori, Chuichiro; Matsuda, Masahisa; Matsuoka, Takeo; Mochinaga, Daizo.
1993-01-01
In the superstring models we have not only the complete 27 multiplets of E 6 but also extra incomplete (27+27-bar) chiral supermultiplets being alive at low energies. Associated with these additional multiplets, when the gauge symmetry contains more than one U(1) gauge group, there may exist gauge kinetic mixings among these U(1) gauge groups. In such cases the effect of gauge kinetic mixings should be incorporated into the study of unification of gauge couplings. We study these interesting effects systematically in these models. The string threshold effect is also taken into account. It is found that in the four-generation models we do not have an advisable solution of string unification of gauge couplings consistent with experimental values at the electroweak scale. We also discuss the possible scenarios to solve this problem. (author)
International Nuclear Information System (INIS)
Mills, R.
1989-01-01
This article is a survey of the history and ideas of gauge theory. Described here are the gradual emergence of symmetry as a driving force in the shaping of physical theory; the elevation of Noether's theorem, relating symmetries to conservation laws, to a fundamental principle of nature; and the force of the idea (''the gauge principle'') that the symmetries of nature, like the interactions themselves, should be local in character. The fundamental role of gauge fields in mediating the interactions of physics springs from Noether's theorem and the gauge principle in a remarkably clean and elegant way, leaving, however, some tantalizing loose ends that might prove to be the clue to a future deeper level of understanding. The example of the electromagnetic field as the prototype gauge theory is discussed in some detail and serves as the basis for examining the similarities and differences that emerge in generalizing to non-Abelian gauge theories. The article concludes with a brief examination of the dream of total unification: all the forces of nature in a single unified gauge theory, with the differences among the forces due to the specific way in which the fundamental symmetries are broken in the local environment
Directory of Open Access Journals (Sweden)
Ebert AD
2008-01-01
Full Text Available In Europa wird die Idee der Qualitätsverbesserung auf dem Gebiet der Endometriose vertieft. Verschiedene "Task Forces" arbeiten mit zum Teil identischen Methoden am gleichen Ziel. Die Bildung spezialisierter Endometriosezentren verbunden mit einer breiten Qualifikation der Ärzte und des medizinischen Personals gehören begleitet von der Unterstützung der Forschung ebenso in dieses Spektrum wie die Schulung und Information der betroffenen Frauen sowie die Sensibilisierung der Gesundheitspolitik, der Kostenträger und der Industrie. Vor dem Hintergrund knapper Ressourcen ist eine Bündelung des vorhandenen nationalen und internationalen Engagements absehbar und notwendig. Inwieweit dies zur konsequenten Gründung von einheitlichen nationalen Endometriose-Gruppen als Basis einer europäischen Dachgesellschaft führen könnte, bleibt abzuwarten. Wünschenswert ist es allemal.
Relativistic Coulomb excitation
International Nuclear Information System (INIS)
Winther, A.; Alder, K.
1979-01-01
Coulomb excitation of both target and projectile in relativistic heavy ion collisions is evaluated including the lowest order correction for the deviation from a straight line trajectory. Explicit results for differential and total cross sections are given in the form of tables and figures. (Auth.)
DEFF Research Database (Denmark)
2016-01-01
The invention relates to a strain gauge of a carrier layer and a meandering measurement grid positioned on the carrier layer, wherein the strain gauge comprises two reinforcement members positioned on the carrier layer at opposite ends of the measurement grid in the axial direction....... The reinforcement members are each placed within a certain axial distance to the measurement grid with the axial distance being equal to or smaller than a factor times the grid spacing. The invention further relates to a multi-axial strain gauge such as a bi-axial strain gauge or a strain gauge rosette where each...... of the strain gauges comprises reinforcement members. The invention further relates to a method for manufacturing a strain gauge as mentioned above....
Coulomb dissociation of N-20,N-21
Roeder, Marko; Adachi, Tatsuya; Aksyutina, Yulia; Alcantara, Juan; Altstadt, Sebastian; Alvarez-Pol, Hector; Ashwood, Nicholas; Atar, Leyla; Aumann, Thomas; Avdeichikov, Vladimir; Barr, M.; Beceiro, Saul; Bemmerer, Daniel; Benlliure, Jose; Bertulani, Carlos; Boretzky, Konstanze; Borge, Maria J. G.; Burgunder, G.; Caamano, Manuel; Caesar, Christoph; Casarejos, Enrique; Catford, Wilton; Cederkall, Joakim; Chakraborty, S.; Chartier, Marielle; Chulkov, Leonid; Cortina-Gil, Dolores; Crespo, Raquel; Pramanik, Ushasi Datta; Diaz-Fernandez, Paloma; Dillmann, Iris; Elekes, Zoltan; Enders, Joachim; Ershova, Olga; Estrade, A.; Farinon, F.; Fraile, Luis M.; Freer, Martin; Freudenberger, M.; Fynbo, Hans; Galaviz, Daniel; Geissel, Hans; Gernhaeuser, Roman; Goebel, Kathrin; Kalantar-Nayestanaki, Nasser; Najafi, Mohammad Ali; Rigollet, Catherine; Stoica, V.; Streicher, Branislav; Van de Walle, J.
2016-01-01
Neutron-rich light nuclei and their reactions play an important role in the creation of chemical elements. Here, data from a Coulomb dissociation experiment on N-20,N-21 are reported. Relativistic N-20,N-21 ions impinged on a lead target and the Coulomb dissociation cross section was determined in a
Ordering in classical Coulombic systems
International Nuclear Information System (INIS)
Schiffer, J. P.
1998-01-01
The author discusses the properties of classical Coulombic matter at low temperatures. It has been well known for some time [1,2] that infinite Coulombic matter will crystallize in body-centered cubic form when the quantity Λ (the dimensionless ratio of the average two-particle Coulomb energy to the kinetic energy per particle) is larger than approximately175. But the systems of such particles that have been produced in the laboratory in ion traps, or ion beams, are finite with surfaces defined by the boundary conditions that have to be satisfied. This results in ion clouds with sharply defined curved surfaces, and interior structures that show up as a set of concentric layers that are parallel to the outer surface. The ordering does not appear to be cubic, but the charges on each shell exhibit a ''hexatic'' pattern of equilateral triangles that is the characteristic of liquid crystals. The curvature of the surfaces prevents the structures on successive shells from interlocking in any simple fashion. This class of structures was first found in simulations [3] and later in experiments [4
Generalized coherent states for the Coulomb problem in one dimension
International Nuclear Information System (INIS)
Nouri, S.
2002-01-01
A set of generalized coherent states for the one-dimensional Coulomb problem in coordinate representation is constructed. At first, we obtain a mapping for proper transformation of the one-dimensional Coulomb problem into a nonrotating four-dimensional isotropic harmonic oscillator in the hyperspherical space, and the generalized coherent states for the one-dimensional Coulomb problem is then obtained in exact closed form. This exactly soluble model can provide an adequate means for a quantum coherency description of the Coulomb problem in one dimension, sample for coherent aspects of the exciton model in one-dimension example in high-temperature superconductivity, semiconductors, and polymers. Also, it can be useful for investigating the coherent scattering of the Coulomb particles in one dimension
International Nuclear Information System (INIS)
Kummer, W.; Mistelberger, H.; Schaller, P.; Schweda, M.
1989-01-01
Supersymmetric gauge theories can be suitably quantized in non-supersymmetric 'superaxial' gauges without abolishing the basic advantages of the superfield technique. In this review the state of the art is presented. It includes the proof of renormalization and the proof of gauge independence and supersymmetry of observable physical quantities. (author)
Energy Technology Data Exchange (ETDEWEB)
Oelerich, M. [Inst. fuer Klinische Radiologie der Univ. Muenster (Germany); Mai, R. [Inst. fuer Klinische Radiologie der Univ. Muenster (Germany); Mueller-Miny, H. [Radiologische Klinik der Univ. Bonn (Germany); Peters, P.E. [Inst. fuer Klinische Radiologie der Univ. Muenster (Germany)
1995-10-01
Dysphagia is a common symptom in clinical practice. Due to the broad spectrum of underlying diseases many disciplines are involved in the therapy and diagnosis of dysphagia, where radiology plays a central role. The radiologist is confronted with different diagnostic problems and has to choose the most appropriate type of investigation. In many cases no organic disorder can be demonstrated by clinical examination, endoscopy or conventional radiological techniques. In this setting cineradiography is an outstanding tool for finding functional or structural changes in the swallowing chain. This study underlines the efficiency of cineradiography in the diagnosis of dysphagia. (orig.) [Deutsch] Die Dysphagie ist in der klinischen Praxis ein haeufiges Symptom. Aufgrund des weiten Spektrums zugrundeliegender Erkrankungen sind zahlreiche Fachdisziplinen mit der Diagnostik und Therapie der Dysphagie befasst, wobei der Roentgendiagnostik eine zentrale Rolle zukommt. Der Radiologe wird mit unterschiedlichen Fragestellungen konfrontiert und muss die geeignete Untersuchungsstrategie festlegen. Haeufig ist durch klinische Untersuchung, Endoskopie und konventionelle Roentgenuntersuchung keine organische Erkrankung nachweisbar. Mit der Hochfrequenzkinematographie steht dann ein Verfahren zur Verfuegung, welches in hervorragender Weise funktionelle und strukturelle Veraenderungen der am Schluckakt beteiligten Organe aufzeigen kann. Die hohe Effizienz der Methode wird in dieser Studie belegt. (orig.)
Qualitativ-empirische Forschung in der Psychologie - am Beispiel der Inhaltsanalyse
Mayring, Philipp
1994-01-01
Die letzten Jahre haben eine Fülle an qualitativen Forschungsansätzen, sowohl an Designs als auch an Techniken, in der Psychologie gebracht. Im Vergleich mit der weit zurückreichenden qualitativ-geisteswissenschaftlichen Tradition lassen sich einige neue Merkmale hier herausarbeiten: der empirische Ansatzpunkt, die Betonung der Systematik und Überprüfbarkeit im Vorgehen und die Integrierbarkeit mit quantitativen Ansätzen. Dies soll am Beispiel der qualitativen lnhaltsanalyse verdeutlicht werd...
Coulomb Distortion in the Inelastic Regime
Energy Technology Data Exchange (ETDEWEB)
Patricia Solvignon, Dave Gaskell, John Arrington
2009-09-01
The Coulomb distortion effects have been for a long time neglected in deep inelastic scattering for the good reason that the incident energies were very high. But for energies in the range of earlier data from SLAC or at JLab, the Coulomb distortion could have the potential consequence of affecting the A-dependence of the EMC effect and of the longitudinal to transverse virtual photon absorption cross section ratio $R(x,Q^2)$.
Abelian gauge theories with tensor gauge fields
International Nuclear Information System (INIS)
Kapuscik, E.
1984-01-01
Gauge fields of arbitrary tensor type are introduced. In curved space-time the gravitational field serves as a bridge joining different gauge fields. The theory of second order tensor gauge field is developed on the basis of close analogy to Maxwell electrodynamics. The notion of tensor current is introduced and an experimental test of its detection is proposed. The main result consists in a coupled set of field equations representing a generalization of Maxwell theory in which the Einstein equivalence principle is not satisfied. (author)
Die Bedeutung von Interleukon-1 beo der Entstehung der Knochenerosion
Directory of Open Access Journals (Sweden)
Graninger W
2002-01-01
Full Text Available Die chronische Polyarthritis ist eine immunmediierte entzündliche Erkrankung, die morphologisch durch eine Zerstörung der Gelenksstrukturen und des subchondralen Knochens charakterisiert ist. Obwohl schon in frühen Krankheitsstadien eine gelenksnahe Osteoporose im Nativröntgen sichtbar wird, ist die Richtigkeit der Diagnose radiologisch erst durch den Nachweis jener typischen Knochenzerstörung zu beweisen, die als Usur oder Erosion bezeichnet wird. An der Grenze zwischen dem entzündlichen Zellinfiltrat, das als Pannus makroskopisch und histologisch imponiert, und dem Gelenksknorpel (cartilage-pannus junction kommt es unter dem Einfluß aktivierter Synoviafibroblasten und ihrer Sekretionsprodukte zum Knorpelzelluntergang und zur Zerstörung der Knorpelmatrix. Gleichzeitig kommt es zur Aktivierung von Osteoklasten, die schließlich in der Entstehung der gelenksnahen Erosion und der subchondralen Knochenzysten resultiert.
Energy Technology Data Exchange (ETDEWEB)
Rentz, O.; Fichtner, W.; Frank, M. [Karlsruhe Univ. (T.H.) (Germany). Inst. fuer Industriebetriebslehre und Industrielle Produktion; Wolf, M.A.; Rejman, M.; Eyerer, P. [Fraunhofer-Institut fuer Chemische Technologie (ICT) (Germany); Reimert, R.; Schulz, A.; Buren, V. v. [Karlsruhe Univ. (T.H.) (Germany). Engler-Bunte-Institut Bereich 1 - Gas, Erdoel und Kohle; Schaefers, B.; Bernart, Y. [Karlsruhe Univ. (T.H.) (DE). Institut fuer Soziologie (IfSoz) (Germany)
2002-09-01
Major objectives of this project are: to prepare a cross-disciplinary analysis of all characteristic aspects of the energy supply and demand patterns of a group of selected energy-intensive companies in the Karlsruhe and Rhine harbour area (5 industrial power consumers, 1 utility), to identify practical approaches for optimization and integration of energy and material flows, (networking), and to develop optimised investment and energy supply options within the framework of given conditions. The basis of the optimal solution and energy network presented and explained in detail is a new combined-cycle power plant running as a gas-fired CHP plant, substituting about 50% of the systems formerly used. (orig./CB) [German] Fragestellungen der Effizienzsteigerung und der Verwertung von Abfaellen und Abwaerme gewinnen an Relevanz vor dem Hintergrund der begrenzten Aufnahmekapazitaet der Umweltmedien fuer Schadstoffe. Im Rahmen des Projektes wurde am Beispiel der Region Karlsruhe (5 Industrieunternehmen und 1 EVU) die Entwicklung betriebsuebergreifender Energieversorgungssysteme (Netzwerke) interdisziplinaer analysiert und beschrieben. Zielsetzungen des Projekts waren unter anderem: Bestimmung von zukunftsfaehigen Optionen, intelligente Vernetzung von Energiestroemen, wirtschaftliche Optimierung betriebsuebergreifender Energiemanagement-Loesungen. Die optimale vorgestellte Loesung ist charakterisiert durch den Neubau einer zentralen, gasgefeuerten GuD-Anlage, die etwa die Haelfte der bisherigen Anlagen ersetzt und zusammen mit den weiterhin genutzten Anlagen die Energieversorgung der Unternehmen sicherstellt. (orig./CB)
Energy Technology Data Exchange (ETDEWEB)
Pranzas, P.K. [GKSS-Forschungszentrum Geesthacht GmbH (Germany). Inst. fuer Werkstofforschung
1999-07-01
-Konzentrationen unter der Bildung von Kettenstrukturen oder ungeordneten ROS-Agglomeraten koagulierten. Aus den SANS-Streukurven wurden fuer ausgewaehlte ROS zusaetzlich die mittleren Molekulargewichte berechnet, wobei ebenfalls eine Agglomeratbildung beobachtet wurde. Studien des Koagulationsverhaltens von ROS gegenueber Kupferionen ergaben zusaetzlich zu den kugelfoermigen ROS-Einheiten groessere ROS-Cu{sup 2+}-Agglomerate. Ein linearer Zusammenhang zwischen der Cu{sup 2+}-Zugabe und der Bildung der ROS-Cu{sup 2+}-Agglomerate wurde festgestellt. Mit der Roentgenmikroskopie wurden grossflaechige ROS-Cu{sup 2+}-Netzwerkstrukturen abgebildet. Fuer Quecksilber- und Cadmium-Ionen wurde keine derartige Koagulationswechselwirkung gefunden. Untersuchungen des Koagulationsverhaltens der ROS gegenueber Tensiden mit der Roentgenmikroskopie ergaben bei ansteigenden Konzentrationen des kationischen Standard-Tensids DTB in der ganzen Loesung verteilte mizellartige Strukturen gleicher Groesse sowie groessere Agglomerate bis hin zu Netzwerkstrukturen. Die aufgefuehrten Strukturen zeigen sowohl das Potential des etablierten strukturanalytischen Systems als auch die Komplexitaet und Vielfalt der Koagulationswechselwirkungen von ROS und damit die mannigfaltigen Prozesse im Bereich zwischen geloester Phase und Suspension. (orig.)
Two-center Coulomb problem with Calogero interaction
Energy Technology Data Exchange (ETDEWEB)
Hakobyan, T., E-mail: tigran.hakobyan@ysu.am; Nersessian, A., E-mail: arnerses@ysu.am [Armenia Tomsk Polytechnic University, Yerevan State University (Russian Federation)
2017-03-15
We show that the Calogero-type perturbation preserves the integrability and partial separation of variables for the Stark–Coulomb and two-center Coulomb problems, and present the explicit expressions of their constants of motion. We reveal that this perturbation preserves the spectra of initial systems, but leads to the change of degree of degeneracy.
Auswirkungen der pharmakologischen Osteoporosetherapie in der Zahnheilkunde
Directory of Open Access Journals (Sweden)
Gruber R
2013-01-01
Full Text Available Die pharmakologische Osteoporosetherapie greift systemisch in den Knochenumbau ein und erreicht damit auch den Kieferknochen. Die komplexen Auswirkungen auf die Klinik der Parodontologie und Implantologie werden im vorliegenden Beitrag beispielhaft dargestellt. Vitamin D3 fördert die Heilung nach Parodontalchirurgie. Bisphosphonate können die parodontale Situation während der Nachsorgetherapie verbessern und möglicherweise die Einheilung von dentalen Implantaten fördern. Die meisten klinischen Studien zeigen keine negativen Effekte in Bezug auf die Entstehung von Osteonekrosen des Kieferknochens. Die Bedeutung von Strontium für die Zahnheilkunde ist primär in der Kariesprävention angesiedelt. Erste klinische Pilotstudien unterstützen eine mögliche Wirkung von Teriparatid auf die Einheilung dentaler Implantate. Bedeutsam erscheinen die positiven Effekte von Teriparatid bei der Regeneration nach chirurgischer Parodontaltherapie. Die vorliegenden Studien zeigen, dass die pharmakologische Osteoporosetherapie einen positiven Einfluss auf die Klinik der Parodontologie und Implantologie haben kann.
On Coulomb disintegration of relativistic nuclei and hypernuclei
International Nuclear Information System (INIS)
Lyuboshits, V.L.
1989-01-01
The dependence of the total cross-section of excitation and disintegration of a relativistic nucleus in the Coulomb field on the energy and parameters characterizing nuclear dimensions is investigated. The analogy with the problem of atomic ionization at the passage of charged particles through matter is used. The results are applied to the description of the Coulomb dissociation of nuclei with small binding energies. An explicit expression for the effective cross-section of the Coulomb disintegration of the hypernucleus-Λ 3 H into a deuteron and Λ-particle. 12 refs
International Nuclear Information System (INIS)
Moriyasu, K.
1978-01-01
A pedagogical approach to gauge invariance is presented which is based on the analogy between gauge transformations and relativity. By using the concept of an internal space, purely geometrical arguments are used to teach the physical ideas behind gauge invariance. Many of the results are applicable to general gauge theories
Directory of Open Access Journals (Sweden)
Mario Coletta
2013-01-01
Full Text Available Das vorgeschlagene Thema hat das Ziel, dem Konzept der Landschaft eine neue Definition zu geben. Sie soll nicht nur als Umhuellung des staedtischen und laendlichen Territoriums gesehen werden, das besiedelt und produktiv ist, zivilisiet und natuerlich belassen, sondern wie ein lebender Koerper, wenn auch nicht bei bester Gesundheit, der trotz seines Altes noch den vielen Veraenderungen standhaelt. Veraenderungen durch Naturkatatrophen herforgerufen, und besonders durch die vielen Wunden die das Werk der Menschen ihm zugefuegt hat. Als lebendes Wesen leidet die Landschaft und freut sich in guten Zeiten, kleidert sich lieber arm, aber schicklich, als reich und anmassend: Zeuge guter und schlechter Haushaltsfuehrung, jedoch Erbe einer Geschichte die sie erhebt, die Geschichte, Literatur, Ausdruecke der Kunts, kreative Planung beseelt hat. All das ist zusammengefasst in dem Wort "Kultur", die es verdient hat, erworben zu werden, vertieft und den naeschsten Generationen weitergegeben, moeglicherweise noch bereichert von dem, das die heutige Kultur ausarbeiten kann, auch auf dem Weg der Stadtplanung.
Aktuelles aus der "Fallambulanz Urheberrecht" der OER Community
Directory of Open Access Journals (Sweden)
Angelika Güttl-Strahlhofer
2014-12-01
Full Text Available Im Sommersemester 2014 öffnete die Fallambulanz Urheberrecht der OER Community (Open Educational Resources der Virtuellen Pädagogischen Hochschule (VPH ihre Pforten und behandelte – von LehrerInnen eingelieferte – "PatientInnen" ... Die OER Community wird auch 2015 für alle LehrerInnen offen sein und ist dazu da, die Herausforderungen des Urheberrechts im LehrerInnenberuf wahrzunehmen und gemeinschaftlich Lösungswege zu erarbeiten. Es folgt eine kurze Zusammenfassung der wichtigsten Erkenntnisse der einzelnen Fälle. Für die ausführlicheren Fallbeschreibungen siehe http://www.virtuelle-ph.at/mod/page/view.php?id=50897 oder auch den Diskussionsverlauf im Forum. Neben den Fällen sind noch zwei Werkstattberichte (Bilder-/Musikschwerpunkt und eine OER-Basisinformation ("Tücken freier Bilder" als Ergebnisse der Lernakitvitäten im Sommersemester 2014 beigefügt.
Landschaftsbereiche der Provinz Latina
Directory of Open Access Journals (Sweden)
Luigi Piemontese
2012-08-01
Full Text Available Das Konzept der Landschaft setz sich zusammen aus verschiedenen Bezugspunkten und Interpretationen, je nach dem Blickpunkt, und ihre Wahnehrung veraendert sich je nach der verschiedenartigen Brille mit der man sie sieht. Der Artikel, geht von der Definition der Landschaft aus, wie sie in der Eurpaischen Konvention zitiert ist :“ Ein Teil des Landes, wie es von seinen Volk gesehen ist, dessen Charakter geformt ist aus naturlichen und menschlichen Faktoren und deren Wechselverhaeltnis”. Er wird fortgefuehrt mit der Identifikation der Landschaftsbereiche der Provinz Latina, die angesehn werden sollen als klimatisch, litologisch und morphologisch aenliche Landschaftsportionen, in denen erstens die Merkmale der Flora und Fauna klar werden und an zweiter Stelle, durch den Gebrauch des Territoriums und die Veraendungen mit denen er es gezeichnet hat, das Tun des Menschen. Die Methodik ruht teilweise auf der Klassifizierung des Territoriums, ausgearbeitet von C.Blasio und dem Konkretfall angeglichen.
Der Sport und die traditionelle Bewegungskultur der Aborigines
Wrogemann, Ohle
2001-01-01
Bei mehreren Studienaufenthalten in Australien wurde nach den Betrachtungsweisen der deutschen Sportwissenschaft umfangreiches Material der nachstehenden Quellen gesammelt: persönliche Kontakte zu einzelnen Personen, Besuch von öffentlichen und privaten Institutionen, Verfolgen des aktuellen Mediengeschehens, narrative Interviews mit Aborigines, Gespräche mit Experten unterschiedlicher Fachrichtungen, Politikern und Personen der multikulturellen australischen Gesellschaft, Teilnahme ...
Some observations on interpolating gauges and non-covariant gauges
Indian Academy of Sciences (India)
We discuss the viability of using interpolating gauges to define the non-covariant gauges starting from the covariant ones. We draw attention to the need for a very careful treatment of boundary condition defining term. We show that the boundary condition needed to maintain gauge-invariance as the interpolating parameter ...
Hamacher, Bernd
2008-01-01
Lernet-Holenias „Wahrer Werther“ (1959) ist eine Montage: Der größte Teil des Buches besteht aus einer Wiedergabe der 1774 anonym erschienenen ersten Fassung von Goethes »Leiden des jungen Werthers«. Vorangestellt ist eine aus Heinrich Gloëls Buch »Goethes Wetzlarer Zeit« (1911) kompilierte Einleitung, in der die stofflich-biographischen Hintergründe des Romans aus Goethes Wetzlarer Zeit erzählt werden. Die Montage belegt, dass die Gegenreaktion gegen den „Werther“ auch in der Mitte des 20. J...
Coulomb drag in coherent mesoscopic systems
DEFF Research Database (Denmark)
Mortensen, Asger; Flensberg, Karsten; Jauho, Antti-Pekka
2001-01-01
We present a theory for Coulomb drag between two mesoscopic systems. Our formalism expresses the drag in terms of scattering matrices and wave functions, and its range of validity covers both ballistic and disordered systems. The consequences can be worked out either by analytic means, such as th......We present a theory for Coulomb drag between two mesoscopic systems. Our formalism expresses the drag in terms of scattering matrices and wave functions, and its range of validity covers both ballistic and disordered systems. The consequences can be worked out either by analytic means......, such as the random matrix theory, or by numerical simulations. We show that Coulomb drag is sensitive to localized states. which usual transport measurements do not probe. For chaotic 2D systems we find a vanishing average drag, with a nonzero variance. Disordered 1D wires show a finite drag, with a large variance...
Der Einsatz von E-Portfolios in der Berufsausbildung - Konzeption und Potenziale
Directory of Open Access Journals (Sweden)
Uwe Elsholz
2010-02-01
Full Text Available In der beruflichen Bildung sind (E-Portfolios zur Reflexion des Gelernten – anders als etwa an Hochschulen oder in allgemeinbildenden Schulen – in Theorie und Praxis gegenwärtig kaum existent. Konzepte und Studien zum Einsatz von E-Portfolios in der Berufsausbildung und der Weiterbildung fehlen weitgehend, so dass die Potenziale von Portfolioarbeit für eine selbstbewusstere und selbstbestimmtere Gestaltung beruflichen Lernens bisher ungenutzt bleiben. Hier setzt dieser Beitrag an. Es wird ein Konzept vorgestellt, wie der Einsatz eines E-Portfolios die Berufsausbildung im dualen System unterstützen kann. Anhand des dargestellten Beispiels werden Möglichkeiten und Grenzen des Einsatzes von E-Portfolios in der beruflichen Bildung aufgezeigt. Die Umsetzung des E-Portfolios findet im Rahmen des berufswissenschaftlich begründeten E- Learning-Konzepts der Kompetenzwerkst@tt statt (vgl. Howe/Knutzen 2007. Die Kompetenzwerkst@tt ist ein softwaregestütztes Ausbildungskonzept, das sich an realen beruflichen Arbeitsprozessen und Ansätzen des Situierten Lernens orientiert. Im Mittelpunkt des E-Portfolios als Teil der Kompetenzwerkst@tt steht die lernortübergreifende Dokumentation und Reflexion der Ausbildungsinhalte der Dualen Berufsausbildung. Im Beitrag wird gezeigt, wie die konzeptionellen Überlegungen zur Portfolioarbeit in der beruflichen Bildung vom Portfolio-Diskurs in anderen Bildungsbereichen beeinflusst sind, sich aber in der Umsetzung und in den konkreten Zielsetzungen deutlich unterscheiden. Es werden darüber hinaus weitere Möglichkeiten und Optionen von Portfolioarbeit in der beruflichen Bildung aufgezeigt.
Energy Technology Data Exchange (ETDEWEB)
Fasol, K.H.
1999-07-01
Controlled water turbines were first introduced in the second half of the 19th century. The report takes a look at the history of controlled turbines, including those inventions and technologies that paved the way for water turbines as we know them today and for turbine speed control. The report is based on a lecture presented by the author on 10 Nov 1998 in the opening session of the 10th international seminar on hydroelectric power systems at the university of Vienna. The contents are presented in more detail and illustrated by examples. [German] Seit langem widmen sich Wissenschaftshistoriker und auch Ingenieure der Erforschung und Aufarbeitung der Technikgeschichte als eigenstaendige Disziplin der Wissenschaftsgeschichte, wofuer an vielen Universitaeten und Hochschulen entsprechende Lehrstuehle bestehen. Auch an der Entwicklung der Regelungstechnik im Allgemeinen ist das Interesse mit langem erwacht. Die ersten geregelten Wasserturbinen wurden in der zweiten Haelfte des 19. Jahrhunderts bekannt und so ist es denn auch angebracht, die zumindest 130 Jahre der Entwicklungsgeschichte dieser Turbinenregelung darzustellen. Dies ginge nicht, ohne zunaechst auch auf jene anderen Erfindungen und Technologien kurz zurueckzublicken, die Wegbereiter fuer die heutigen Wasserturbinen und fuer die ersten Ansaetze zu deren Drehzahlregelung waren. Diese Arbeit beruht auf einem Hauptvortrag, der am 10 November 1998 in der Eroeffnungssitzung des 10. Internationalen Seminars Wasserkraftanlagen an der Technischen Universitaet Wien gehalten wurde. Gegenueber der schriftlichen Fassung jenes Vortrags wird mit diesem Heft den an diesem speziellen Sektor der Technikgeschichte interessierten Kollegen eine stark erweiterte Fassung vorgelegt. (orig./GL)
Inflation and gauge mediation in supersymmetric gauge theory
International Nuclear Information System (INIS)
Nakai, Yuichiro; Sakai, Manabu
2011-01-01
We propose a simple high-scale inflationary scenario based on a phenomenologically viable model with direct gauge mediation of low-scale supersymmetry breaking. Hybrid inflation occurs in a hidden supersymmetry breaking sector. Two hierarchical mass scales to reconcile both high-scale inflation and gauge mediation are necessary for the stability of the metastable supersymmetry breaking vacuum. Our scenario is also natural in light of the Landau pole problem of direct gauge mediation. (author)
Empirical Coulomb matrix elements and the mass of 22Al
International Nuclear Information System (INIS)
Whitehead, R.R.; Watt, A.; Kelvin, D.; Rutherford, H.J.
1976-01-01
An attempt has been made to obtain a set of Coulomb matrix elements which fit the known Coulomb energy shifts in the nuclei of mass 18 to 22. The interaction obtained fits the data well with only a few exceptions, one of these being the Coulomb shift of the notorious third 0 + state in 18 Ne. These Coulomb matrix elements are used together with the Chung-Wildenthal interaction to obtain a new prediction for the mass excess of 22 Al. The results indicate that 22 Al should be bound against proton emission. (Auth.)
Gauge-invariant dynamical quantities of QED with decomposed gauge potentials
International Nuclear Information System (INIS)
Zhou Baohua; Huang Yongchang
2011-01-01
We discover an inner structure of the QED system; i.e., by decomposing the gauge potential into two orthogonal components, we obtain a new expansion of the Lagrangian for the electron-photon system, from which, we realize the orthogonal decomposition of the canonical momentum conjugate to the gauge potential with the canonical momentum's two components conjugate to the gauge potential's two components, respectively. Using the new expansion of Lagrangian and by the general method of field theory, we naturally derive the gauge invariant separation of the angular momentum of the electron-photon system from Noether theorem, which is the rational one and has the simplest form in mathematics, compared with the other four versions of the angular momentum separation available in literature. We show that it is only the longitudinal component of the gauge potential that is contained in the orbital angular momentum of the electron, as Chen et al. have said. A similar gauge invariant separation of the momentum is given. The decomposed canonical Hamiltonian is derived, from which we construct the gauge invariant energy operator of the electron moving in the external field generated by a proton [Phys. Rev. A 82, 012107 (2010)], where we show that the form of the kinetic energy containing the longitudinal part of the gauge potential is due to the intrinsic requirement of the gauge invariance. Our method provides a new perspective to look on the nucleon spin crisis and indicates that this problem can be solved strictly and systematically.
International Nuclear Information System (INIS)
Weinberg, S.
1976-01-01
The problem of how gauge symmetries of the weak interactions get broken is discussed. Some reasons why such a heirarchy of gauge symmetry breaking is needed, the reason gauge heirarchies do not seem to arise in theories of a given and related type, and the implications of theories with dynamical symmetry breaking, which can exhibit a gauge hierarchy
Local gauge coupling running in supersymmetric gauge theories on orbifolds
International Nuclear Information System (INIS)
Hillenbach, M.
2007-01-01
By extending Feynman's path integral calculus to fields which respect orbifold boundary conditions we provide a straightforward and convenient framework for loop calculations on orbifolds. We take advantage of this general method to investigate supersymmetric Abelian and non-Abelian gauge theories in five, six and ten dimensions where the extra dimensions are compactified on an orbifold. We consider hyper and gauge multiplets in the bulk and calculate the renormalization of the gauge kinetic term which in particular allows us to determine the gauge coupling running. The renormalization of the higher dimensional theories in orbifold spacetimes exhibits a rich structure with three principal effects: Besides the ordinary renormalization of the bulk gauge kinetic term the loop effects may require the introduction of both localized gauge kinetic terms at the fixed points/planes of the orbifold and higher dimensional operators. (orig.)
Local gauge coupling running in supersymmetric gauge theories on orbifolds
Energy Technology Data Exchange (ETDEWEB)
Hillenbach, M.
2007-11-21
By extending Feynman's path integral calculus to fields which respect orbifold boundary conditions we provide a straightforward and convenient framework for loop calculations on orbifolds. We take advantage of this general method to investigate supersymmetric Abelian and non-Abelian gauge theories in five, six and ten dimensions where the extra dimensions are compactified on an orbifold. We consider hyper and gauge multiplets in the bulk and calculate the renormalization of the gauge kinetic term which in particular allows us to determine the gauge coupling running. The renormalization of the higher dimensional theories in orbifold spacetimes exhibits a rich structure with three principal effects: Besides the ordinary renormalization of the bulk gauge kinetic term the loop effects may require the introduction of both localized gauge kinetic terms at the fixed points/planes of the orbifold and higher dimensional operators. (orig.)
Coulomb Dissociation as a Tool of Nuclear Astrophysics
International Nuclear Information System (INIS)
Utsunomiya, H.
2000-01-01
My talk will begin with an introduction of the Coulomb dissociation method, proceed to discussions on Coulomb breakup of 7 Li with respect to the big-bang nucleosynthesis and end with the revision of astrophysical S-factors. The methodology based on the virtual photon source will be introduced in view of experimental techniques. The discussion will include the quantum tunnelling effect in non-resonant breakup, the lifetime of continuum states, and Coulomb distortion of relevant cross sections. Roles of multi-step processes and different multipolarities will also be discussed on the basis of solving a time-dependent Schroedinger equation. My talk will present quantitative results. The theoretical framework of the Coulomb dissociation method and a broad scope of its applications are given by G. Baur. Applications to radioactive nuclei which have quickly become vogue are discussed in the related lecture of J. Kiener. (author)
Energy Technology Data Exchange (ETDEWEB)
Soehndel, B. [Zweckverband Restmuellheizkraftwerk, Boeblingen (Germany); Faulstich, M. [Technische Univ. Muenchen, Garching (Germany). Lehrstuhl fuer Wasserguete- und Abfallwirtschaft
1998-09-01
There are various financing and organisation models in use at German waste treatment plants. These models have an influence on capital costs as well as on operating costs. The great variety of existing models, which is not only found in theory but also in practice, is a sure indication that there is no universal solution at present but that models always have to be adapted to the current conditions governing the plant in question (e.g., tax law amendments). In view of the great complexity of this subject the following deliberations will be restricted to only the best-known types of financing model. [Deutsch] Fuer den Betrieb von Abfallbehandlungsanlagen gibt es bundesweit verschiedene Organisations- und Finanzierungsmodelle. Diese Modelle haben Auswirkungen auf die Kapitalkosten und die Betriebskosten. Die Vielfalt der nicht nur theoretisch moeglichen, sondern auch der in der Praxis existierenden Modelle ist mit Sicherheit ein Hinweis, dass derzeit keine universelle Loesung moeglich ist, sondern diese immer den aktuellen und spezifischen Verhaeltnissen (z.B. Steuerrechtsaenderung u.a.) angepasst werden muss. Auf Grund der Komplexibilitaet beschraenken sich die nachfolgenden Ausfuehrungen ausschliesslich auf die bekanntesten Formen der Finanzierungsmodelle. (orig./SR)
Energy Technology Data Exchange (ETDEWEB)
Dieterle, W.; Dilger, E. [Bosch (R.) GmbH, Gerlingen (Germany). Zentralbereich Forschung und Vorausentwicklung; Buerger, K.G. [Bosch (R.) GmbH (Germany)
2001-04-01
The ever increasing requirements with respect to fuel consumption, emissions as well as safety and comfort necessitate ever increasing complex functionalities in the car. They are realized, as a rule, by a combination of mechanics, hydraulics, electrics/electronics and, more and more, software. In the past, the development of the various electric/electronic, mechanical or hydraulic components tended to happen at separate levels, nowadays the focus is more on a comprehensive approach to the overall system. In this context, the integrated development of 'mechatronic' components, including the respective software, leads to a targeted solution. (orig.) [German] Staendig steigende Anforderungen hinsichtlich Kraftstoffverbrauch, Emissionen sowie Sicherheit und Komfort bedingen immer komplexere Funktionalitaeten im Kraftfahrzeug. Sie werden in der Regel durch eine Kombination von Mechanik, Hydraulik, Elektrik/Elektronik und zunehmend auch Software realisiert. Nachdem in der Vergangenheit die Entwicklung meist noch auf getrennten Ebenen verlief, steht heute ein uebergreifender, das Gesamtsystem umfassender Ansatz im Vordergrund. Dieser Beitrag der Robert Bosch GmbH berichtet ueber aktuelle Mechatronik-Entwicklungen. Dabei sorgt die integrierte Entwicklung der 'mechatronischen' Komponenten unter Einbezug der zugehoerigen Software fuer eine zielgerichtete Loesung. (orig.)
Coulomb sum rules in the relativistic Fermi gas model
International Nuclear Information System (INIS)
Do Dang, G.; L'Huillier, M.; Nguyen Giai, Van.
1986-11-01
Coulomb sum rules are studied in the framework of the Fermi gas model. A distinction is made between mathematical and observable sum rules. Differences between non-relativistic and relativistic Fermi gas predictions are stressed. A method to deduce a Coulomb response function from the longitudinal response is proposed and tested numerically. This method is applied to the 40 Ca data to obtain the experimental Coulomb sum rule as a function of momentum transfer
Solution of the gauge identities in the axial gauge
International Nuclear Information System (INIS)
Delbourgo, R.
1981-01-01
Starting from the spectral representation of the two-point functions in the axial gauge, the gauge identities are solved so as to express the higher-point Green functions linearly in terms of the two-point spectral function. The four-point functions are an important input for investigations of scalar electrodynamics and vector chromodynamics based on the gauge technique. (author)
Energy Technology Data Exchange (ETDEWEB)
Loebel, K.H. [Inst. fuer Markscheidewesen und Geodaesie, TU Bergakademie Freiberg (Germany); Fenk, J. [Inst. fuer Markscheidewesen und Geodaesie, TU Bergakademie Freiberg (Germany)
1995-01-01
abzuschaetzen. Eine Ende der siebziger Jahre ausgearbeitete Loesung zur Berechnung von Tagesbruechen wurde in vielen Positionen verbessert und im Anwendungsbereich erweitert. Diese neue Loesung wurde in ein Programm fuer PC-Technik umgesetzt. Um die Bruchgefaehrdung als Grundlage fuer die Raumplanung auf der Basis von modernen Geo-Informations-Systemen (GIS) verfuegbar zu haben, muss die vorliegende Software in ein raumbezogenes Modell eingebunden werden. Fuer eine flaechenhafte Auswertung in einem Untersuchungsgebiet koennen aus diesem Modell die bruchrelevanten Daten entlang der Streckenachsen selektiert und die Bruchparameter prognostiziert werden. Als Ergebnis der Berechnungen wird eine Topologie zu erwartender Bruchdurchmesser und Bruchvolumina mit Farbcodierung der Teufe, in der der Bruchprozess gegebenenfalls zum Erliegen kommt, entlang der Spur des Streckensystems abgeleitet, welche eine Einschaetzung der Gefaehrdung bereits vorhandener Objekte bzw. weitere Planungen in einem GIS ermoeglicht. (orig.)
Hofer, Andi; Pivarci, Pavol
2010-01-01
Die qualitative Studie «Reflexion in der Praxis der Sozialen Arbeit» basiert auf der Annahme, dass ein unterschiedliches Verständnis zu einer unterschiedlichen Umsetzung der Reflexion führt. Reflexion ist jedoch ein gefordertes Qualitätskriterium der Sozialen Arbeit. In der relevanten Literatur ist Reflexion ein Bestandteil des methodischen Handelns und wird als Evaluation oder reflexive Aufgabenbearbeitung definiert, wobei sie durch individuelle und institutionelle Faktoren wechselseitig bed...
International Nuclear Information System (INIS)
Mack, G.
1982-01-01
After a description of a pure Yang-Mills theory on a lattice, the author considers a three-dimensional pure U(1) lattice gauge theory. Thereafter he discusses the exact relation between lattice gauge theories with the gauge groups SU(2) and SO(3). Finally he presents Monte Carlo data on phase transitions in SU(2) and SO(3) lattice gauge models. (HSI)
International Nuclear Information System (INIS)
Nielsen, H.B.; Brene, N.
1984-12-01
The fundamental laws of nature may be truely random, or they may be so complicated that a random description is adequate. With this philosophy we examine various ways in which a lattice gauge theory (at the Planck scale) can be generalized. Without here giving up a regular lattice structure (which we really ought to do) we consider two generalizations. Making the action (quenched) random has the effect that the gauge group tends to break down and some gauge bosons become massive, unless the gauge group has special properties: no noncentral corners in the geometry of conjugacy classes and furthermore a connected center. Making the concept of gauge transformation more general has a symmetry breaking effect for groups with outer automorphisms. A study of SU 5 -breaking in the context of the first breakdown mechanism (D. Bennett, E. Buturovic and H. B. Nielsen) is shortly reviewed. (orig.)
Coulomb displacement energies in nuclei: a new approach
International Nuclear Information System (INIS)
Auerbach, N.; Tel Aviv Univ.; Bernard, V.; Nguyen, V.G.
1978-04-01
The neutron core polarization gives rise to an important correction to the direct Coulomb contribution when one calculates the Coulomb displacement energies. In the Hartree-Fock model it is shown that this correction is about 2% to 4.5% in medium and heavy nuclei. The core polarization as well as other higher order effects can be included by using a selfconsistent description of the analog state in a complete proton particle-neutron hole space. The Coulomb displacement energies in 48 Ca, 88 Sr and 208 Pb have been calculated using Skyrme interactions SIII and SIV. A good agreement with experiment is obtained
Coulomb effects in relativistic laser-assisted Mott scattering
International Nuclear Information System (INIS)
Ngoko Djiokap, J.M.; Kwato Njock, M.G.; Tetchou Nganso, H.M.
2004-09-01
We reconsider the influence of the Coulomb interaction on the process of relativistic Mott scattering in a powerful electromagnetic plane wave for which the ponderomotive energy is of the order of the magnitude of the electron's rest mass. Coulomb effects of the bare nucleus on the laser-dressed electron are treated more completely than in the previous work of Li et al. [J. Phys. B: At. Mol. Opt. Phys. 37 (2004) 653]. To this end we use Coulomb-Dirac-Volkov functions to describe the initial and the final states of the electron. First-order Born differential cross sections of induced and inverse bremsstrahlung are obtained for circularly and linearly polarized laser light. Numerical calculations are carried out from both polarizations, for various nucleus charge values, three angular configurations and an incident energy in the MeV range. It is found that for parameters used in the present work, incorporating Coulomb effects of the target nucleus either in the initial state or in the final state yields cross sections which are quite similar whatever the scattering geometry and polarization considered. When Coulomb distortions are included in both states, the cross sections are strongly modified with the increase of Z, as compared to the outcome of the prior form of the T-matrix treatment. (author)
Electromagnetic velocity gauge: use of multiple gauges, time response, and flow perturbations
International Nuclear Information System (INIS)
Erickson, L.M.; Johnson, C.B.; Parker, N.L.; Vantine, H.C.; Weingart, R.C.; Lee, R.S.
1981-01-01
We have developed an in-situ electromagnetic velocity (EMV) gauge system for use in multiple-gauge studies of initiating and detonating explosives. We have also investigated the risetime of the gauge and the manner in which it perturbs a reactive flow. We report on the special precautions that are necessary in multiple gauge experiments to reduce lead spreading, simplify target fabrication problems and minimize cross talk through the conducting explosive. Agreement between measured stress records and calculations from multiple velocity gauge data give us confidence that our velocity gauges are recording properly. We have used laser velocity interferometry to measure the gauge risetime in polymethyl methacrylate (PMMA). To resolve the difference in the two methods, we have examined hydrodynamic and material rate effects. In addition, we considered the effects of shock tilt, electronic response and magntic diffusion on the gauge's response time
Ginzburg criterion for ionic fluids: the effect of Coulomb interactions.
Patsahan, O
2013-08-01
The effect of the Coulomb interactions on the crossover between mean-field and Ising critical behavior in ionic fluids is studied using the Ginzburg criterion. We consider the charge-asymmetric primitive model supplemented by short-range attractive interactions in the vicinity of the gas-liquid critical point. The model without Coulomb interactions exhibiting typical Ising critical behavior is used to calibrate the Ginzburg temperature of the systems comprising electrostatic interactions. Using the collective variables method, we derive a microscopic-based effective Hamiltonian for the full model. We obtain explicit expressions for all the relevant Hamiltonian coefficients within the framework of the same approximation, i.e., the one-loop approximation. Then we consistently calculate the reduced Ginzburg temperature t(G) for both the purely Coulombic model (a restricted primitive model) and the purely nonionic model (a hard-sphere square-well model) as well as for the model parameters ranging between these two limiting cases. Contrary to the previous theoretical estimates, we obtain the reduced Ginzburg temperature for the purely Coulombic model to be about 20 times smaller than for the nonionic model. For the full model including both short-range and long-range interactions, we show that t(G) approaches the value found for the purely Coulombic model when the strength of the Coulomb interactions becomes sufficiently large. Our results suggest a key role of Coulomb interactions in the crossover behavior observed experimentally in ionic fluids as well as confirm the Ising-like criticality in the Coulomb-dominated ionic systems.
Grundlagen der ultraschallgezielten transurethralen Stammzelltherapie der Harn-Inkontinenz
Directory of Open Access Journals (Sweden)
Strasser H
2005-01-01
Full Text Available In präklinischen Studien wurden Sicherheit und Durchführbarkeit von durch transurethralen Ultraschall geführten Injektionen von autologen Myo- und Fibroblasten zur Behandlung der Stressinkontinenz untersucht. Zwischen 2002 und März 2005 wurden 129 inkontinente Patienten (Alter 3685 Jahre, 92 Frauen, 37 Männer in eine klinische Studie aufgenommen, um zu untersuchen, ob die Stressinkontinenz effektiv mittels durch transurethralen Ultraschall geführte Injektionen von autologen Myo- und Fibroblasten behandelt werden kann. Die Patienten litten an Stress- oder gemischter Harninkontinenz. Vor und nach der Therapie wurden ein definierter Inkontinenz-Score, Veränderungen der Lebensqualität sowie Morphologie und Funktion von Urethra und Rhabdosphinkter bewertet. Der transurethrale Ultraschall wurde zur Untersuchung und Visualisierung des unteren Harntraktes verwendet. Zusätzlich wurden vor und nach der Behandlung urodynamische und Labortests durchgeführt. Es wurden kleine Muskelbiopsien am Oberarm unter Lokalanästhesie entnommen und die Zellen in einem GMP-Labor zum Wachstum gebracht. Die Fibroblasten wurden fallweise mit einer kleinen Menge an Kollagen als Trägermaterial (ca. 2,5 ml gemischt. Mittels transurethralem Ultraschall und einer speziell entwickelten Injektionsvorrichtung wurden die Fibroblasten in die urethrale Mukosa zur Atrophiebehandlung injiziert. Die Myoblasten wurden direkt in den Rabdosphinkter zur Muskelrekonstruktion injiziert. Bei 108 Patienten konnte die Harninkontinenz nach der Injektion geheilt werden. Die postoperative Lebensqualität sowie die Dicke von Urethra und Rhabdosphinkter und die Aktivität und Kontraktilität des Rhabdosphinkter waren nach der Behandlung wesentlich verbessert. Bei 21 Patienten kam es zu einer Verbesserung der Harninkontinenz. Es traten keine Nebenwirkungen oder Komplikationen auf.
Der evolutionäre Naturalismus in der Ethik
Kaiser, Marie I.
Charles Darwin hat eindrucksvoll gezeigt, dass der Mensch ebenso wie alle anderen Lebewesen ein Produkt der biologischen Evolution ist. Die sich an Darwin anschließende Forschung hat außerdem plausibel gemacht, dass sich nicht nur viele der körperlichen Merkmale des Menschen, sondern auch (zumindest einige) seiner Verhaltensdispositionen in adaptiven Selektionsprozessen herausgebildet haben. Die Vorstellung, dass auch die menschliche Moralität evolutionär bedingt ist, scheint daher auf den ersten Blick ganz überzeugend. Schließlich hat die Evolutionstheorie in den vergangenen Jahrzehnten in vielen Bereichen (auch außerhalb der Biologie) ihre weitreichende Bedeutung unter Beweis gestellt. Warum sollte, so könnte man beispielsweise fragen, gerade die Fähigkeit des Menschen, moralische Normen aufzustellen und gemäß ihnen zu handeln, nicht evolutionär erklärt werden können? Und warum sollte eine solche evolutionäre Erklärung der menschlichen Moralität irrelevant für die Rechtfertigung moralischer Normen sein? Warum sollte die Ethik eine Bastion der Philosophen bleiben, für die evolutionsbiologische Forschungsergebnisse über den Menschen und seine nächsten Verwandten keinerlei Relevanz besitzen?
Appleberry, W. T.
1983-01-01
Standard hydraulic shock absorber modified to form coulomb (linear friction) damper. Device damps very small velocities and is well suited for use with large masses mounted on soft springs. Damping force is easily adjusted for different loads. Dampers are more reliable than fluid dampers and also more economical to build and to maintain.
Gauge symmetry breaking in gauge theories -- in search of clarification
Friederich, Simon
2013-01-01
The paper investigates the spontaneous breaking of gauge symmetries in gauge theories from a philosophical angle, taking into account the fact that the notion of a spontaneously broken local gauge symmetry, though widely employed in textbook expositions of the Higgs mechanism, is not supported by
Some observations on interpolating gauges and non-covariant gauges
International Nuclear Information System (INIS)
Joglekar, Satish D.
2003-01-01
We discuss the viability of using interpolating gauges to define the non-covariant gauges starting from the covariant ones. We draw attention to the need for a very careful treatment of boundary condition defining term. We show that the boundary condition needed to maintain gauge invariance as the interpolating parameter θ varies, depends very sensitively on the parameter variation. We do this with a gauge used by Doust. We also consider the Lagrangian path-integrals in Minkowski space for gauges with a residual gauge-invariance. We point out the necessity of inclusion of an ε-term (even) in the formal treatments, without which one may reach incorrect conclusions. We, further, point out that the ε-term can contribute to the BRST WT-identities in a non-trivial way (even as ε → 0). We point out that these contributions lead to additional constraints on Green's function that are not normally taken into account in the BRST formalism that ignores the ε-term, and that they are characteristic of the way the singularities in propagators are handled. We argue that a prescription, in general, will require renormalization; if at all it is to be viable. (author)
Effective potential for spontaneously broken gauge theories and gauge hierarchies
International Nuclear Information System (INIS)
Hagiwara, T.; Ovrut, B.
1979-01-01
The Appelquist-Carazzone effective-field-theory method, where one uses effective light-field coupling constants dependent on the heavy-field sector, is explicitly shown to be valid for the discussion of the gauge-hierarchy problem in grand unified gauge models. Using the method of functionals we derive an expression for the one-loop approximation to the scalar-field effective potential for spontaneously broken theories in an arbitrary R/sub xi/ gauge. We argue that this potential generates, through its derivatives, valid zero-momentum, one-particle-irreducible vertices for any value of xi (not just the xi→infinity Landau gauge). The equation that the one-loop vacuum correction must satisfy is presented, and we solve this equation for a number of spontaneously broken theories including gauge theories with gauge groups U(1) and SO(3). We find that a one-loop vacuum shift in a massless, non-Goldstone direction occurs via the Coleman-Weinberg mechanism with an effective coupling constant dependent on the heavy-field sector
Geschwisterbeziehungen in der Verarbeitung sexueller Traumatisierung: Der Film "Das Fest"
Sohni, Hans
2001-01-01
Filme reizen als Gegenstand psychoanalytischer Kunstinterpretation durch ihre strukturelle Nähe zum "szenischen Verstehen" und bereichern unsere Einsicht in menschliche Beziehungen. Der Film "Das Fest" lohnt wegen seiner besonderen ästhetischen Form und wegen seiner Aussage zur Geschwisterbeziehung. Nach filmjournalistischer Einschätzung zeigt er die Demontage der bürgerlichen Gesellschaft und die Reinszenierung destruktiver Gewalt. In der Interpretation dieses Beitrags führt der Film dagegen...
Coulomb corrections for interferometry analysis of expanding hadron systems
Energy Technology Data Exchange (ETDEWEB)
Sinyukov, Yu.M.; Lednicky, R.; Pluta, J.; Erazmus, B. [Centre National de la Recherche Scientifique, 44 - Nantes (France). Lab. de Physique Subatomique et des Technologies Associees; Akkelin, S.V. [ITP, Kiev (Ukraine)
1997-09-01
The problem of the Coulomb corrections to the two-boson correlation functions for the systems formed in ultra-relativistic heavy ion collisions is considered for large effective system volumes. The modification of the standard zero-distance correction (so called Gamow or Coulomb factor) has been proposed for such a kind of systems. For the {pi}{sup +}{pi}{sup +} and K{sup +}K{sup +} correlation functions the analytical calculations of the Coulomb correction are compared with the exact numerical results. (author). 20 refs.
Quantum Monte Carlo calculations of van der Waals interactions between aromatic benzene rings
Azadi, Sam; Kühne, T. D.
2018-05-01
The magnitude of finite-size effects and Coulomb interactions in quantum Monte Carlo simulations of van der Waals interactions between weakly bonded benzene molecules are investigated. To that extent, two trial wave functions of the Slater-Jastrow and Backflow-Slater-Jastrow types are employed to calculate the energy-volume equation of state. We assess the impact of the backflow coordinate transformation on the nonlocal correlation energy. We found that the effect of finite-size errors in quantum Monte Carlo calculations on energy differences is particularly large and may even be more important than the employed trial wave function. In addition to the cohesive energy, the singlet excitonic energy gap and the energy gap renormalization of crystalline benzene at different densities are computed.
Coulomb Mediated Hybridization of Excitons in Coupled Quantum Dots.
Ardelt, P-L; Gawarecki, K; Müller, K; Waeber, A M; Bechtold, A; Oberhofer, K; Daniels, J M; Klotz, F; Bichler, M; Kuhn, T; Krenner, H J; Machnikowski, P; Finley, J J
2016-02-19
We report Coulomb mediated hybridization of excitonic states in optically active InGaAs quantum dot molecules. By probing the optical response of an individual quantum dot molecule as a function of the static electric field applied along the molecular axis, we observe unexpected avoided level crossings that do not arise from the dominant single-particle tunnel coupling. We identify a new few-particle coupling mechanism stemming from Coulomb interactions between different neutral exciton states. Such Coulomb resonances hybridize the exciton wave function over four different electron and hole single-particle orbitals. Comparisons of experimental observations with microscopic eight-band k·p calculations taking into account a realistic quantum dot geometry show good agreement and reveal that the Coulomb resonances arise from broken symmetry in the artificial semiconductor molecule.
Coulomb matrix elements in multi-orbital Hubbard models.
Bünemann, Jörg; Gebhard, Florian
2017-04-26
Coulomb matrix elements are needed in all studies in solid-state theory that are based on Hubbard-type multi-orbital models. Due to symmetries, the matrix elements are not independent. We determine a set of independent Coulomb parameters for a d-shell and an f-shell and all point groups with up to 16 elements (O h , O, T d , T h , D 6h , and D 4h ). Furthermore, we express all other matrix elements as a function of the independent Coulomb parameters. Apart from the solution of the general point-group problem we investigate in detail the spherical approximation and first-order corrections to the spherical approximation.
Planar density of vacuum charge induced by a supercritical Coulomb potential
Directory of Open Access Journals (Sweden)
V.R. Khalilov
2017-06-01
Full Text Available Analytical expressions for the planar density of an induced vacuum charge are obtained in a strong Coulomb potential in coordinate space. Treatment is based on a self-adjoint extension approach for constructing of the Green's function of a charged fermion in an external electromagnetic field. Induced vacuum charge density is calculated and analyzed in subcritical and supercritical Coulomb potentials for massless and massive fermions. We argue that the virtual and so-called real vacuum polarizations contribute in an induced vacuum charge in a supercritical Coulomb potential. The behavior of the polarization vacuum charge density is investigated at long and short distances from the Coulomb center. The induced vacuum charge has a screening sign. Screening of a Coulomb impurity in graphene is briefly discussed. The real vacuum polarization charge density that acquires the quantum electrodynamics vacuum in a supercritical Coulomb potential due to the real vacuum polarization is calculated. It is shown that the vacuum charge densities essentially differ in massive and massless cases. We expect that our results can, as a matter of principle, be tested in graphene with a supercritical Coulomb impurity.
Planar density of vacuum charge induced by a supercritical Coulomb potential
Energy Technology Data Exchange (ETDEWEB)
Khalilov, V.R., E-mail: khalilov@phys.msu.ru; Mamsurov, I.V.
2017-06-10
Analytical expressions for the planar density of an induced vacuum charge are obtained in a strong Coulomb potential in coordinate space. Treatment is based on a self-adjoint extension approach for constructing of the Green's function of a charged fermion in an external electromagnetic field. Induced vacuum charge density is calculated and analyzed in subcritical and supercritical Coulomb potentials for massless and massive fermions. We argue that the virtual and so-called real vacuum polarizations contribute in an induced vacuum charge in a supercritical Coulomb potential. The behavior of the polarization vacuum charge density is investigated at long and short distances from the Coulomb center. The induced vacuum charge has a screening sign. Screening of a Coulomb impurity in graphene is briefly discussed. The real vacuum polarization charge density that acquires the quantum electrodynamics vacuum in a supercritical Coulomb potential due to the real vacuum polarization is calculated. It is shown that the vacuum charge densities essentially differ in massive and massless cases. We expect that our results can, as a matter of principle, be tested in graphene with a supercritical Coulomb impurity.
Neue Medien unter der Organisationsperspektive. Eine empirische Untersuchung in der Weiterbildung
Directory of Open Access Journals (Sweden)
Richard Stang
2017-08-01
Full Text Available Gesellschaftliche Modernisierungsprozesse haben zu immensen Veränderungsprozessen auf allen Ebenen gesellschaftlichen Lebens geführt. Wirtschaft, Politik, Bildungswesen etc. sind als Gesamtsysteme davon betroffen, genauso wie die Institutionen und Organisationen, die in deren Rahmen agieren. Stehr (2000, S. 17 spricht davon, dass wir uns in einem „Übergangsstadium zwischen zwei Gesellschaftsformationen“ befinden und meint damit den Übergang von der „Industriegesellschaft“ zur „Wissensgesellschaft“, in der Wissen konstitutiv für die Gesellschaftsformation ist. Mit dem Bedeutungszuwachs der Ressource „Wissen“ gehen Prozesse der voranschreitenden gesellschaftlichen Ausdifferenzierung einher. So unterschiedlich die sozialwissenschaftlichen Analysen der Gesellschaftsformation und die daraus gefolgerten theoretischen Konstrukte auch sein mögen (vgl. u.a. Beck 1986, Castells 2001, Gross 1994, Schulze 1993, wird doch in einem besonderen Maße die Entwicklung von Technik, besonders der Informations- und Kommunikationstechniken (im Folgenden: Neuen Medien, als ein wichtiger Motor der gesellschaftlichen Veränderungsprozesse gesehen. Besonders Castells (2001 hat die gesellschaftliche, kulturelle und ökonomische Bedeutung der Neuen Medien in seiner Studie über die Netzwerkgesellschaft eindrucksvoll herausgearbeitet.
Cavity QED experiments with ion Coulomb crystals
DEFF Research Database (Denmark)
Herskind, Peter Fønss; Dantan, Aurélien; Marler, Joan
2009-01-01
Cavity QED experimental results demonstrating collective strong coupling between ensembles of atomic ions cooled into Coulomb crystals and optical cavity fields have been achieved. Collective Zeeman coherence times of milliseconds have furthermore been obtained.......Cavity QED experimental results demonstrating collective strong coupling between ensembles of atomic ions cooled into Coulomb crystals and optical cavity fields have been achieved. Collective Zeeman coherence times of milliseconds have furthermore been obtained....
Hegel und die Opferung der Philosophie: Dialektik der Ästhetik und Politik
Directory of Open Access Journals (Sweden)
Jovanov Rastko
2013-01-01
Full Text Available Dem Aufsatz liegen folgende Fragen zugrunde: Ist es gerechtfertigt, vom Erbe der tragischen Darstellung des Kampfes im Hegelschen Begriff der Philosophie und insbesondere in seiner Konzeption der Dialektik als Bewegung und Geschichtlichkeit des absoluten Geistes zu sprechen? Hat der Versöhnungsbegriff Hegels, der am konkretesten innerhalb des philosophischen Gedankens ausgeführt wird, bestimmte Folgen auch für den Begriff der Philosophie selber? Opfert sich die Philosophie einer endlichen Äußerlichkeit oder bedarf sie selbst eines Opfers, um das philosophische System als solches zu vervollständigen? Kann man auch heutzutage die geschichtlich-politischen Ereignisse und die Vergehen des Rechts als tragisch darstellen und betrachten? Vermag es die Politik noch immer (wie in der Moderne, die Rolle des Schicksals in der griechischen Tragödie zu übernehmen? Auf solche Fragen werden hier keine endgültigen Antworten gegeben, es wird vielmehr der Rahmen für weitere Betrachtungen bereitgestellt - innerhalb oder außerhalb der Philosophie Hegels. [Projekat Ministarstva nauke Republike Srbije, br. 179049: Politike društvenog pamćenja i nacionalnog identiteta: regionalni i evropski kontekst
Introduction to gauge theories
International Nuclear Information System (INIS)
Wit, B. de
1983-01-01
In these lectures we present the key ingredients of theories with local gauge invariance. We introduce gauge invariance as a starting point for the construction of a certain class of field theories, both for abelian and nonabelian gauge groups. General implications of gauge invariance are discussed, and we outline in detail how gauge fields can acquire masses in a spontaneous fashion. (orig./HSI)
Coulomb dissociation of N 20,21
Röder, Marko; Adachi, Tatsuya; Aksyutina, Yulia; Alcantara, Juan; Altstadt, Sebastian; Alvarez-Pol, Hector; Ashwood, Nicholas; Atar, Leyla; Aumann, Thomas; Avdeichikov, Vladimir; Barr, M.; Beceiro, Saul; Bemmerer, Daniel; Benlliure, Jose; Bertulani, Carlos
2016-01-01
Neutron-rich light nuclei and their reactions play an important role in the creation of chemical elements. Here, data from a Coulomb dissociation experiment on N20,21 are reported. Relativistic N20,21 ions impinged on a lead target and the Coulomb dissociation cross section was determined in a kinematically complete experiment. Using the detailed balance theorem, the N19(n,γ)N20 and N20(n,γ)N21 excitation functions and thermonuclear reaction rates have been determined. The N19(n,γ)N20 rate is...
Coulomb singularity effects in tunnelling spectroscopy of individual impurities
Arseyev, P. I.; Maslova, N. S.; Panov, V. I.; Savinov, S. V.
2002-01-01
Non-equilibrium Coulomb effects in resonant tunnelling processes through deep impurity states are analyzed. It is shown that Coulomb vertex corrections to the tunnelling transfer amplitude lead to a power-law singularity in current- voltage characteristics
International Nuclear Information System (INIS)
Becchi, C.; Rouet, A.; Stora, R.
1975-10-01
Stora's analysis is continued in discussing the nonabelian (Yang-Mills) gauge field models (G.F.M.). The gauge independence of the physical scattering operator is discussed in some details and the connection between its unitary and the Slavnov symmetry outlined. Only the models involving semisimple gauge groups are considered. This greatly simplifies the analysis of the possible quantum corrections to the Quantum Action Principle which is reduced to the study of the cohomology group of the Lie algebra characterizing the gauge theory. The discussion is at the classical level for the algebraic properties of the SU(2) Higgs-Kibble-Englert-Brout-Faddeev-Popov lagrangian and its invariance under Slavnov identity transformations is exhibited. The renormalization of the Slavnov identity in the G.M.F. involving semisimple gauge groups is studied. The unitary and gauge independence of the physical S operator in the SU(2) H.K. model is dealt with [fr
Zero energy gauge fields and the phases of a gauge theory
International Nuclear Information System (INIS)
Guendelman, E.I.
1990-01-01
A new approach to the definition of the phases of a Poincare invariant gauge theory is developed. It is based on the role of gauge transformations that change the asymptotic value of the gauge fields from zero to a constant. In the context of theories without Higgs fields, this symmetry can be spontaneously broken when the gauge fields are massless particles, explicitly broken when the gauge fields develop a mass. Finally, the vacuum can be invariant under this transformation, this last case can be achieved when the theory has a violent infrared behavior, which in some theories can be connected to a confinement mechanism
Gauge fixing conditions for the SU(3) gauge theory
International Nuclear Information System (INIS)
Ragiadakos, Ch.; Viswanathan, K.S.
1979-01-01
SU(3) gauge theory is quantized in the temporal gauge A 0 =0. Gauge fixing conditions are imposed completely on the electric field components, conjugate to the vector potential Ssub(i) that belongs to the subalgebra SO(3) of SU(3). The generating functional in terms of the independent variables is derived. It is ghost-free and may be regarded as a theory of (non-relativistic) spin-0, 1, 2, and 3 fields. (Auth.)
Critical opalescence in the pure Coulomb system
Energy Technology Data Exchange (ETDEWEB)
Bobrov, V.B., E-mail: vic5907@mail.r [Joint Institute for High Temperatures, Russian Academy of Sciences, Izhorskaia St., 13, Bd. 2. Moscow 125412 (Russian Federation); Trigger, S.A., E-mail: satron@mail.r [Joint Institute for High Temperatures, Russian Academy of Sciences, Izhorskaia St., 13, Bd. 2. Moscow 125412 (Russian Federation); Institut fuer Physik, Humboldt-Universitaet zu Berlin, Newtonstrasse 15, D-12489 Berlin (Germany)
2011-04-18
Highlights: The review of the critical opalescence problem is presented. Light scattering in a two-component electron-nuclear system is studied. The exact relations between the structure factors and compressibility are found. The obtained relations are valid for strong interaction for the Coulomb systems. The experimental verification of these relations is possible for various elements. - Abstract: Based on the dielectric formalism and quantum field theory methods, the phenomenon of critical opalescence is explained for light scattering in pure matter as a two-component electron-nuclear system with Coulomb interaction. A similar phenomenon is shown to occur in the case of neutron scattering in pure substances as well. The obtained results are valid for quantum case and arbitrary strong Coulomb interaction. Thus, the relations between structure factors derived for the electron-nuclear system are the exact result of the quantum statistical mechanics.
Residual gauge invariance of Hamiltonian lattice gauge theories
International Nuclear Information System (INIS)
Ryang, S.; Saito, T.; Shigemoto, K.
1984-01-01
The time-independent residual gauge invariance of Hamiltonian lattice gauge theories is considered. Eigenvalues and eigenfunctions of the unperturbed Hamiltonian are found in terms of Gegengauer's polynomials. Physical states which satisfy the subsidiary condition corresponding to Gauss' law are constructed systematically. (orig.)
Das Smart Meter Gateway - Der kritische Erfolgsfaktor für die Digitalisierung der Energiewende
Abs, Paul-Vincent
Der kritische Erfolgsfaktor der Digitalisierung in der Energiewirtschaft liegt im bevorstehenden hohen Investitionsvolumen und der Beherrschung der neuen Technik. Ein Weg zur Kostenminimierung liegt im Zusammenschluss der einzelnen Akteure, um gemeinsame Skalenvorteile zu heben. Auch bieten neue Geschäftsmodelle die Möglichkeit, zusätzliche Erlöse zu generieren.
Coulomb energy of uniformly charged spheroidal shell systems.
Jadhao, Vikram; Yao, Zhenwei; Thomas, Creighton K; de la Cruz, Monica Olvera
2015-03-01
We provide exact expressions for the electrostatic energy of uniformly charged prolate and oblate spheroidal shells. We find that uniformly charged prolate spheroids of eccentricity greater than 0.9 have lower Coulomb energy than a sphere of the same area. For the volume-constrained case, we find that a sphere has the highest Coulomb energy among all spheroidal shells. Further, we derive the change in the Coulomb energy of a uniformly charged shell due to small, area-conserving perturbations on the spherical shape. Our perturbation calculations show that buckling-type deformations on a sphere can lower the Coulomb energy. Finally, we consider the possibility of counterion condensation on the spheroidal shell surface. We employ a Manning-Oosawa two-state model approximation to evaluate the renormalized charge and analyze the behavior of the equilibrium free energy as a function of the shell's aspect ratio for both area-constrained and volume-constrained cases. Counterion condensation is seen to favor the formation of spheroidal structures over a sphere of equal area for high values of shell volume fractions.
Regularization of the Coulomb scattering problem
International Nuclear Information System (INIS)
Baryshevskii, V.G.; Feranchuk, I.D.; Kats, P.B.
2004-01-01
The exact solution of the Schroedinger equation for the Coulomb potential is used within the scope of both stationary and time-dependent scattering theories in order to find the parameters which determine the regularization of the Rutherford cross section when the scattering angle tends to zero but the distance r from the center remains finite. The angular distribution of the particles scattered in the Coulomb field is studied on rather a large but finite distance r from the center. It is shown that the standard asymptotic representation of the wave functions is inapplicable in the case when small scattering angles are considered. The unitary property of the scattering matrix is analyzed and the 'optical' theorem for this case is discussed. The total and transport cross sections for scattering the particle by the Coulomb center proved to be finite values and are calculated in the analytical form. It is shown that the effects under consideration can be important for the observed characteristics of the transport processes in semiconductors which are determined by the electron and hole scattering by the field of charged impurity centers
Energy Technology Data Exchange (ETDEWEB)
Diebold, T.; Jacobi, V.; Ballenberger, S.; Hochmuth, K.; Balzer, J.O.; Vogl, T.J. [Inst. fuer Diagnostische und Interventionelle Radiologie, Klinikum der J.W.G.-Univ. Frankfurt/Main (Germany); Krapfl, E.; Minckwitz, G. v.; Solbach, C.; Kaufmann, M. [Klinik fuer Gynaekologie und Geburtshilfe, Klinikum der J.W.G.-Univ. Frankfurt/Main (Germany); Fellbaum, M. [Senckenbergisches Inst. fuer Pathologie, Klinikum der J.W.G.-Univ. Frankfurt/Main (Germany)
2003-04-01
Purpose: To evaluate the potential of stereotactic vacuum breast biopsy in the histologic evaluation of suspicious mammographic findings (BI-RADS{sup TM} IV). Materials und Methods: In 221 patients with 227 probable mammographic lesions categorized as (BI-RADS{sup TM}-IV), stereotactic biopsies were performed with an 11-gauge vacuum-assisted biopsy device (Mammotome). The evaluation included the histology of the specimens obtained with the Mammotome or with surgery, the time for the biopsy, the amount of bleeding, number of rotations and procured specimens, the extent of the resection and the complications. Results: The biopsies were technically successful in 214 of the 227 probable mammographic lesions, with 176 lesions mostly resected and 34 lesions removed more than 50%. No representative tissue was obtained from 4 lesions. All biopsies were performed without any clinically relevant complications and terminated after adequate material was obtained (Oe 28 specimens, 2.58 rotations). The mean time needed for performing the biopsy was 40.2 minutes. The histologic findings were DCIS (42 lesions), ADH (7 lesions), LCIS (3 lesions), ID-Ca (14 lesions), IL-Ca (3 lesions), and IDL-Ca (1 lesion). In 28 of 42 lesions with the initial DCIS histology, the surgical histology was also DCIS (n=28) or no residual tumor (n=10). In 4 lesions with an initial DCIS-histology, the surgical histology was invasive ductal cancer (9.5%). The late follow-up examinations (up to 3 years) did not find any evidence of a false negative biopsy. Conclusion: Stereotactic vacuum breast biopsy ideally complements existing breast biopsy methods. The method is minimal invasive with a low rate of mostly minor complications. (orig.) [German] Ziel: Evaluierung der Wertigkeit der stereotaktischen Vakuumbiopsie zur Abklaerung von Befunden der Kategorie BI-RADS{sup TM} IV in der Mammographie. Material und Methode: Bei 221 Patientinnen mit 227 mammographischen Laesionen der BI-RADS{sup TM}-Kategorie IV
Directory of Open Access Journals (Sweden)
Gruschka M
2009-01-01
Full Text Available Die radikale Prostatektomie ohne Nerverhalt geht mit Impotenz einher. Bei nerverhaltendem Vorgehen kann das Risiko der erektilen Dysfunktion gesenkt, aber nicht ausgeschlossen werden. Die präoperative Beratung der Patienten erfordert bei nerverhaltender Prostatektomie die Kenntnis der Faktoren, die Einfluss auf die postoperative Potenz haben. Patienten & Methoden: 110 Patienten antworteten 24 Monate nach radikaler perinealer nerverhaltender Prostatektomie auf einen per Post übermittelten Fragebogen. Die Patienten wurden, entsprechend dem Erection Hardness Score, nach der Rigidität ihrer Erektionen befragt. Überwiegend erfolgte der Nerverhalt unilateral (104/110. Verschiedene potenzielle Risikofaktoren (Alter, Qualität der präoperativen Erektion, Serum-PSA, Gleason-Score, Tumorvolumen, Prostatavolumen, adjuvante Strahlentherapie, ASA-Score, Chronic Disease Score [CDS], arterielle Hypertonie, Hypercholesterinämie, Diabetes mellitus, KHK, Nikotinkonsum wurden univariat mit der postoperativ erzielten Potenz korreliert. Multivariat wurden dann jene Parameter untersucht, die in der univariaten Analyse einen signifikanten (p ≤ 0,05 oder einen tendenziellen Zusammenhang (p ≤ 0,2 mit der postoperativen erektilen Funktion aufwiesen. Ergebnisse:Das Alter (p 0,001 und der ASAScore (p = 0,018 waren in der univariaten Analyse negative Prädiktoren der postoperativen Potenz. In der multivariaten Analyse war lediglich das Alter (p = 0,028 von signifikanter Bedeutung. Mit jedem Lebensjahr der Männer steigt das Risiko einer um eine Stufe im EHS schlechteren Erektion um das 1,128-Fache an. Bei einem Altersunterschied von 10 Jahren ist das Risiko eines postoperativ schlechteren Erektionsvermögens um den Faktor 3,334 erhöht, bei einem um 20 Jahre höheren Alter beträgt dieser Faktor 11,121. Diskussion & Praxisrelevanz: Das Lebensalter der Patienten wurde im Einklang mit der Literatur als signifikanter Faktor für die postoperative Potenz identifiziert
SCHULDUNFÄHIGE TÄTER IM STRAFRECHT UND IN DER RICHTERLICHEN RECHTSPRECHUNG DER REPUBLIK KROATIEN
Directory of Open Access Journals (Sweden)
Dražen Tripalo
2017-01-01
Full Text Available In der Arbeit wird die Gesetzesregulative hinsichtlich der Lage schuldunfähiger Täter aus der Perspektive des materiellen Strafrechtes und des Strafprozessrechtes sowie auch aus der Perspektive des Gesetzes über den Schutz von Personen mit seelischen Störungen dargestellt. Ebenfalls wird die Anwendung genannter Gesetzesvorschriften in der Rechtsprechung durch die Analyse von 25 rechtskräftigen Strafurteilen gegenüber schuldunfähigen Personen besprochen. Das Ziel dieser Darstellung und Analyse ist es, sowohl Best-Practice-Beispiele richterlicher Rechtsprechung als auch falsche Urteile und die Abweichungen zwischen ihnen festzustellen, um die Qualität der Urteile zu sichern und die Rechtsprechung anzugleichen. Die Urteile werden hinsichtlich der Anwendung von Gesetzesbegriffen, Vollständigkeit der Rechtsprechung, Begründung der Entscheidungen über Verhandlungen in Abwesenheit des Angeklagten, Form der Ausführung des Angeklagten und der Entscheidungen über Kosten analysiert. Besonderen Wert legt man in der Arbeit der Qualität von Entscheidungen über die Anordnung psychiatrischer Behandlung, weil diese Entscheidungen sehr oft nicht klar auf Gesetzesmerkmale hinweisen und ungenügend begründet sind.
Mahnig, Hans
2007-01-01
Der Bericht, vom Bundesamt für Flüchtlinge (BFF) in Auftrag gegeben, stellt eine politikwissenschaftliche Analyse der Vernehmlassung zum Bericht Arbenz vom Mai 1995 dar, welche parallel zur Auswertung durch das BFF selbst unternommen wurde. Er hat zum Ziel, die zentralen Konflikt- und Konsensfelder in der gegenwärtigen migrationspolitischen Auseinandersetzung der Schweiz herauszuarbeiten. Die wichtigsten Resultate der Analyse sind die folgenden: Die Internationale Flüchtlingspolitik und die A...
Usability-Studie zu KonSearch : Evaluation der neuen Literatursuchmaschine der Universität Konstanz
Luca, Helena
2011-01-01
Der vorliegende Bericht beschreibt Hintergründe, Methodik und Ergebnisse einer Usability-Evaluation, die im Sommersemester 2011 im Zuge der Einführung der Literatursuchmaschine KonSearch an der Universität Konstanz durchgeführt wurde. Die neue Suchmaschine basiert auf dem Resource Discovery Service Summon der Firma SerialsSolutions. Sie soll den Benutzern der Bibliothek der Universität Konstanz eine effektive, effiziente und zufriedenstellende Suche nach wissenschaftlichen Informationen ermög...
Characterization of ion Coulomb crystals in a linear Paul trap
International Nuclear Information System (INIS)
Okada, K.; Takayanagi, T.; Wada, M.; Ohtani, S.; Schuessler, H. A.
2010-01-01
We describe a simple and fast method for simulating observed images of ion Coulomb crystals. In doing so, cold elastic collisions between Coulomb crystals and virtual very light atoms are implemented in a molecular dynamics (MD) simulation code. Such an approach reproduces the observed images of Coulomb crystals by obtaining density plots of the statistics of existence of each ion. The simple method has the advantage of short computing time in comparison with previous calculation methods. As a demonstration of the simulation, the formation of a planar Coulomb crystal with a small number of ions has been investigated in detail in a linear ion trap both experimentally and by simulation. However, also large Coulomb crystals including up to 1400 ions have been photographed and simulated to extract the secular temperature and the number of ions. For medium-sized crystals, a comparison between experiments and calculations has been performed. Moreover, an MD simulation of the sympathetic cooling of small molecular ions was performed in order to test the possibility of extracting the temperature and the number of refrigerated molecular ions from crystal images of laser-cooled ions. Such information is basic to studying ultracold ion-molecule reactions using ion Coulomb crystals including sympathetically cooled molecular ions.
Menz, Markus; Kunisch, Sven; Collis, David J.
2015-01-01
Sie werden als Zeichen von Leistung und Erfolg bewundert, aber auch als Ort der Machtkämpfe und Bürokratie misstrauisch beäugt. Haben Konzernzentralen in Zeiten der digitalen Vernetzung und der Globalisierung noch einen Sinn?
Coulomb effects in deuteron stripping reactions as a three-body problem
International Nuclear Information System (INIS)
Osman, A.
1981-08-01
Deuteron stripping nuclear reactions are reconsidered as a three-body problem. The Coulomb effects between the proton and the target nucleus are investigated. The mathematical formalism introduces three-body integral equations which can be exactly calculated for such simple models. These coupled integral equations suitably include the Coulomb effects due to replusive or attractive Coulomb potential. Numerical calculations of the differential cross-sections of the reactions 28 Si(d,p) 29 Si and 40 Ca(d,p) 41 Ca are carried out showing the importance of the Coulomb effects. The angular distributions of these reactions are theoretically calculated and fitted to the experimental data. From this fitting, reasonable spectroscopic factors are obtained. Inclusion of Coulomb force in the three-body model are found to improve the results by a percentage of about 6.826%. (author)
Saumets, Andres
2003-01-01
Ettekanne sümpoosionilt: Gemeinsames Symposium der Evangelisch-Theologischen Fakultät der Universität Tartu, der Estnischen Studiengesellschaft für Morgenlandkunde und der Deutschen Religionsgeschichtlichen Studiengesellschaft. Tartu, 2001
Der Vertragsarzt als Schlüsselfigur der Leistungsversorgung
Gassner, Ulrich M. (Prof.)
2010-01-01
Der Vertragsarzt als Schlüsselfigur der Leistungsversorgung. - In: Tıpta işbirliği ve hukuksal sorunlar = Delegation und Kooperation im Gesundheitswesen / ed.: Hakan Hakeri ... - Samsun : Adalet, 2010. - S. 209-222
Optimierung der Gesichtsklassifikation bei der Erkennung von Akromegalie
Directory of Open Access Journals (Sweden)
Frohner R
2013-01-01
Full Text Available In vorausgegangenen Studien konnte gezeigt werden, dass eine Gesichtsklassifikation mittels Gesichtsphotographien zur Diagnostik von Akromegalie mit guten Ergebnissen eingesetzt werden kann. In diesem Artikel werden die grundlegende Vorgehensweise der Klassifikation mittels der Software FIDA erläutert sowie Optimierungsansätze mit dem Ziel diskutiert, diese Methode näher an den klinischen Einsatz zu bringen. Die Gesichtsklassifikation basiert auf Knotenpunkten, die verteilt über die jeweilige Frontal- und/oder Seitenansicht des Gesichts platziert werden und den so genannten Graphen bilden. Mittels mathematischer Verfahren erfolgt eine Analyse der zugrunde liegenden Textur des Bildes sowie die Auswertung geometrischer Informationen. Untersucht wird, wie sich die Reduktion von als irrelevant eingestuften Knoten auf das Klassifikationsergebnis auswirkt. Ebenso wird untersucht, wie sich neu definierte Knoten, die die typischen morphologischen Veränderungen der akromegalen Erkrankung im Gesicht berücksichtigen, auf die Klassifizierungsergebnisse auswirken. Die interne Validierung erfolgt an einem Datenset bestehend aus 57 an Akromegalie erkrankten Probanden (29 weiblich, 28 männlich sowie 59 Kontrollen (29 weiblich, 30 männlich. Die externe Validierung wird an einer weiteren Stichprobe gemessen, die zum Zeitpunkt der Präsentation auf der Tagung der European Neuroendocrine Association 2012 in Wien 13 akromegale Patienten (7 weiblich, 6 männlich sowie 45 Kontrollen (25 weiblich, 20 männlich umfasste. Die Datenbank wird ständig durch neue Probanden aus verschiedenen Quellen erweitert. Erste Ergebnisse zeigen, dass die Verwendung von Graphen mit reduzierten Knoten und von neuen Sets von Knoten unter Einbeziehung typischer morphologischer Veränderungen des Gesichts die Klassifizierung weiter verbessert. Diese Ergebnisse ermutigen zu weiteren Untersuchungen an einer erweiterten Datenbank.
Verein der Kohlenimporteure. Annual report 2002; Verein der Kohlenimporteure. Jahresbericht 2002
Energy Technology Data Exchange (ETDEWEB)
NONE
2003-07-01
Energy economy developments of the world, the European Union and the Federal Republic of Germany are gone into. The main aspects discussed are the coal market and trade which depends on political decisions and concepts, but also on the availability of other primary energy sources such as oil and nuclear power. The situation of the various countries in the field of coal is illustrated by so-called country reports. [German] Es wird auf die energiewirtschaftliche Entwicklung sowohl der Welt als auch der Europaeischen Union und speziell der Bundesrepublik Deutschland eingegangen. Im Vordergrund steht dabei der Kohlenmarkt und -handel, der von politischen Erscheinungen und Konzepten abhaengig ist, aber auch von der Entwicklung anderer Primaerenergien wie Oel und Kernkraft. In den sogenannten Laenderberichten wird die kohlewirtschaftliche Diskussion einzelner Laender behandelt.
Regularization of the light-cone gauge gluon propagator singularities using sub-gauge conditions
Energy Technology Data Exchange (ETDEWEB)
Chirilli, Giovanni A.; Kovchegov, Yuri V.; Wertepny, Douglas E. [Department of Physics, The Ohio State University,191 W Woodruff Ave, Columbus, OH 43210 (United States)
2015-12-21
Perturbative QCD calculations in the light-cone gauge have long suffered from the ambiguity associated with the regularization of the poles in the gluon propagator. In this work we study sub-gauge conditions within the light-cone gauge corresponding to several known ways of regulating the gluon propagator. Using the functional integral calculation of the gluon propagator, we rederive the known sub-gauge conditions for the θ-function gauges and identify the sub-gauge condition for the principal value (PV) regularization of the gluon propagator’s light-cone poles. The obtained sub-gauge condition for the PV case is further verified by a sample calculation of the classical Yang-Mills field of two collinear ultrarelativistic point color charges. Our method does not allow one to construct a sub-gauge condition corresponding to the well-known Mandelstam-Leibbrandt prescription for regulating the gluon propagator poles.
Directory of Open Access Journals (Sweden)
Kuljić Todor
2012-01-01
Full Text Available Der folgende Text gehört zur kritischen Thanatologie. In allen bekannten Kulturen wurden Normen für den guten und den schlechten Tod von der herrschenden normativen Thanatologien aufgestellt und Kontrollmechanismen installiert. Prämortales und postmortales soziales Sterben ist eine Art der Exklusion der Anderen und wird unterschiedlich bestimmt: als damnatio memoriae, atlantische Sklaventum, Randständigkeit, Isolation oder als Rollenverlust. Das soziale Tod hat einen Klassenaspekt, als den ganzen Klassen Gedächtnis entnommen wurde. Hier werden nur einige Arten und Beispilen des sozialen Mord kritisch erörtert: damnatio memoriae, politische Mord und Sklaventum. Es handelt sich um die institutionelle Verarbeitung und Kodierung von Sterben und Tod durch Staat, Religion und Politik. In der Geschichte sind verschieden Völkern und Klasssen einem intensiveren sozialen Sterbeprozess und der sozialen Tötung unterworfen. Mit Identitätszerstörung der Beherrschten ist das soziale mit dem physischen Sterben harmonischer zu verbinden. Es ist auch auf die Differenz zwischen sozialen und politischen Tötung hingewiesen. Am Ende sind einige Aspekte der heutigen geheimen Tötung erwähnt. [Projekat Ministarstva nauke Republike Srbije, br. 149005: Društveni akteri i društvene promene u Srbiji 1990-2010
Verantwortlicher Umgang mit Antibiotika: Notwendigkeit der Antibiotikareduktion in der Aknetherapie.
Gollnick, Harald P M; Buer, Jan; Beissert, Stefan; Sunderkätter, Cord
2016-12-01
Der übermäßige oder unkritische weltweite Einsatz von Antibiotika in der Medizin hat die Ausbreitung von Antibiotikaresistenzen beschleunigt. In einigen Bereichen sind viele Antibiotika bei bakteriellen Infektionen, die zuvor noch gut auf antibakterielle Wirkstoffe reagierten, mittlerweile wirkungslos geworden. Dermatologen/Venerologen setzten orale und topische Antibiotika bei der Behandlung von Acne vulgaris routinemäßig ein, obwohl Akne weder eine infektiöse Erkrankung ist noch alleine durch das Propionibacterium getriggert wird. Vielmehr ist sie eine komplexe, chronische entzündliche Hauterkrankung, die durch verschiedene pathogenetische Faktoren wie follikuläre Hyperkeratose, erhöhter Sebumproduktion, bakterielle Proliferation und Entzündung zustande kommt. Folglich sollte eine erfolgreiche Therapie auf die Bekämpfung verschiedener pathogenetischer Faktoren und nicht nur auf die von Propionibacterium acnes abzielen. Daher wurden topische Retinoide und Benzoylperoxid als Mittel der ersten Wahl definiert. Monotherapien mit lokalen Antibiotika sollten insgesamt vermieden werden. Systemische Antibiotika der Tetrazyklin-Gruppe haben bei bestimmen Krankheitsstadien ihren Sinn, ihre Wirkung könnte aber eher auf der antientzündlichen als auf der antibiotischen Reaktion beruhen. Gesundheitsbehörden ermahnen alle Gesundheitsdienstleister, den Einsatz von Antibiotika einzuschränken. Das Nutzen-Risiko-Verhältnis muss bei der Entscheidung für oder gegen eine antibiotische Therapie bei einem einzelnen Patienten immer auch in Bezug auf das öffentliche Interesse am Erhalt der Wirksamkeit von Antibiotika abgewogen werden. Im Folgenden werden das aktuelle Krankheitskonzept zu Acne vulgaris und die sich daraus ableitenden Konsequenzen für den Einsatz von Antibiotika vorgestellt. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.
3D Oscillator and Coulomb Systems reduced from Kahler spaces
Nersessian, Armen; Yeranyan, Armen
2003-01-01
We define the oscillator and Coulomb systems on four-dimensional spaces with U(2)-invariant Kahler metric and perform their Hamiltonian reduction to the three-dimensional oscillator and Coulomb systems specified by the presence of Dirac monopoles. We find the Kahler spaces with conic singularity, where the oscillator and Coulomb systems on three-dimensional sphere and two-sheet hyperboloid are originated. Then we construct the superintegrable oscillator system on three-dimensional sphere and ...
Search for a new gauge boson in $\\pi^{0}$ decays
Altegoer, J.; Autiero, D.; Baldisseri, A.; Baldo-Ceolin, M.; Ballocchi, G.; Banner, M.; Basa, S.; Bassompierre, G.; Benslama, K.; Besson, N.; Bird, I.; Blumenfeld, Barry J.; Bobisut, F.; Bouchez, J.; Boyd, S.; Bueno, A.; Bunyatov, S.; Camilleri, L.; Cardini, A.; Castera, A.; Cattaneo, P.W.; Cavasinni, V.; Cervera-Villanueva, A.; Collazuol, G.M.; Conforto, G.; Conta, C.; Contalbrigo, M.; Cousins, R.; Daniels, D.; De Santo, A.; Del Prete, T.; Dignan, T.; Di Lella, L.; do Couto e Silva, E.; Donnelly, I.J.; Dumarchez, J.; Fazio, T.; Feldman, G.J.; Ferrari, R.; Ferrere, D.; Flaminio, V.; Fraternali, M.; Gaillard, J-M.; Galumian, P.; Gangler, E.; Geiser, A.; Geppert, D.; Gibin, D.; Gninenko, S.N.; Gomez-Cadenas, J.J.; Gosset, J.; Gossling, C.; Gouanere, M.; Grant, A.; Graziani, G.; Guglielmi, A.; Hagner, C.; Hernando, J.; Hubbard, D.; Hurst, P.; Hyett, N.; Iacopini, E.; Joseph, C.; Kekez, D.; Khomenko, B.; Kirsanov, M.M.; Klimov, O.; Kokkonen, J.; Kovzelev, A.V.; Kuznetsov, V.; Lacaprara, S.; Lanza, A.; La Rotonda, L.; Laveder, M.; Letessier-Selvon, A.; Levy, J-M.; Linssen, L.; Ljubicic, A.; Long, J.; Lupi, A.; Manola-Poggioli, E.; Marchionni, A.; Martelli, F.; Mechain, X.; Mendiburu, J.P.; Meyer, J.P.; Mezzetto, M.; Mishra, S.R.; Moorhead, G.F.; Mossuz, L.; Nedelec, P.; Nefedov, Yu.; Nguyen-Mau, C.; Orestano, D.; Pastore, F.; Peak, L.S.; Pennacchio, E.; Perroud, J.P.; Pessard, H.; Petti, R.; Placci, A.; Plothow-Besch, H.; Pluquet, A.; Polesello, G.; Pollmann, D.; Pope, B.G.; Popov, B.; Poulsen, C.; Rathouit, P.; Roda, C.; Rubbia, A.; Salvatore, F.; Scannicchio, D.; Schahmaneche, K.; Schmidt, B.; Sconza, A.; Serrano, M.; Sevior, M.E.; Sillou, D.; Soler, F.J.P.; Sozzi, G.; Steele, D.; Steffen, P.; Steininger, M.; Stiegler, U.; Stipcevic, M.; Stolarczyk, T.; Tareb-Reyes, M.; Taylor, G.N.; Tereshchenko, S.; Toropin, A.N.; Touchard, A.M.; Tovey, S.N.; Tran, M.T.; Tsesmelis, E.; Ulrichs, J.; Uros, V.; Valdata-Nappi, M.; Valuev, V.; Vannucci, F.; Varvell, K.E.; Veltri, M.; Vercesi, V.; Verkindt, D.; Vieira, J.M.; Vinogradova, T.; Vo, M.K.; Volkov, S.A.; Weber, F.; Weisse, T.; Werlen, M.; Wilson, F.; Winton, L.J.; Yabsley, Bruce D.; Zaccone, H.; Zuber, K.
1998-01-01
A search was made for a new light gauge boson $X$ which might be produced in $\\pi^{0}\\rightarrow\\gamma + X$ decay from neutral pions generated by 450-GeV protons in the CERN SPS neutrino target. Th e X's would penetrate the downstream shielding and be observed in the NOMAD detector via the Primakoff effect, in the process of $X \\rightarrow\\pi^{0}$ conversion in the external Coulomb field of a nucleus.\\ With $1.45\\times10^{18}$ protons on target, 20 candidate events with energy between 8 and 140 GeV were found from the analysis of neutrino data.\\ This number is in agreement with the e xpectation of 18.1$\\pm$2.8 background events from standard neutrino processes.\\ A new 90 $\\% ~C.L.$ upper limit on the branching ratio $Br(\\pi^{0}\\rightarrow\\gamma + X)<$ (3.3~to~1.9)$\\times10^{-5}$ for $X$ masses ranging from 0 to 120 MeV/c$^{2}$ is obtained.
Plasmon mass scale in two-dimensional classical nonequilibrium gauge theory
Lappi, T.; Peuron, J.
2018-02-01
We study the plasmon mass scale in classical gluodynamics in a two-dimensional configuration that mimics the boost-invariant initial color fields in a heavy-ion collision. We numerically measure the plasmon mass scale using three different methods: a hard thermal loop (HTL) expression involving the quasiparticle spectrum constructed from Coulomb gauge field correlators, an effective dispersion relation, and the measurement of oscillations between electric and magnetic energies after introducing a spatially uniform perturbation to the electric field. We find that the HTL expression and the uniform electric field measurement are in rough agreement. The effective dispersion relation agrees with other methods within a factor of 2. We also study the dependence on time and occupation number, observing similar trends as in three spatial dimensions, where a power-law dependence sets in after an occupation-number-dependent transient time. We observe a decrease of the plasmon mass squared as t-1 / 3 at late times.
Bölscher, Jens; Dumm, Michaela; Suthfeldt, René; Vogt, Benjamin; Bölscher, Judith; Terytze, Konstantin; Schulte, Achim
2017-01-01
Der vorliegende Bericht behandelt die Ergebnisse des Forschungsprojektes RUBUS, welches im Zeitraum November 2013 bis November 2015 von der Freien Universität Berlin durchgeführt wurde. Gegenstand des Projektes ist die Untersuchung der aktuellen Belastungssituation und der Dynamik der Sedimente in der Rummelsburger Bucht als Teil der urbanen Spree in Berlin. Das Projekt hat die Klärung der räumlichen Verteilung, Quantifizierung und Bewertung der Schadstoffbelastung in den Sedimenten der Ru...
Computational assignment of redox states to Coulomb blockade diamonds.
Olsen, Stine T; Arcisauskaite, Vaida; Hansen, Thorsten; Kongsted, Jacob; Mikkelsen, Kurt V
2014-09-07
With the advent of molecular transistors, electrochemistry can now be studied at the single-molecule level. Experimentally, the redox chemistry of the molecule manifests itself as features in the observed Coulomb blockade diamonds. We present a simple theoretical method for explicit construction of the Coulomb blockade diamonds of a molecule. A combined quantum mechanical/molecular mechanical method is invoked to calculate redox energies and polarizabilities of the molecules, including the screening effect of the metal leads. This direct approach circumvents the need for explicit modelling of the gate electrode. From the calculated parameters the Coulomb blockade diamonds are constructed using simple theory. We offer a theoretical tool for assignment of Coulomb blockade diamonds to specific redox states in particular, and a study of chemical details in the diamonds in general. With the ongoing experimental developments in molecular transistor experiments, our tool could find use in molecular electronics, electrochemistry, and electrocatalysis.
Correlated Coulomb Drag in Capacitively Coupled Quantum-Dot Structures.
Kaasbjerg, Kristen; Jauho, Antti-Pekka
2016-05-13
We study theoretically Coulomb drag in capacitively coupled quantum dots (CQDs)-a bias-driven dot coupled to an unbiased dot where transport is due to Coulomb mediated energy transfer drag. To this end, we introduce a master-equation approach that accounts for higher-order tunneling (cotunneling) processes as well as energy-dependent lead couplings, and identify a mesoscopic Coulomb drag mechanism driven by nonlocal multielectron cotunneling processes. Our theory establishes the conditions for a nonzero drag as well as the direction of the drag current in terms of microscopic system parameters. Interestingly, the direction of the drag current is not determined by the drive current, but by an interplay between the energy-dependent lead couplings. Studying the drag mechanism in a graphene-based CQD heterostructure, we show that the predictions of our theory are consistent with recent experiments on Coulomb drag in CQD systems.
Directory of Open Access Journals (Sweden)
Jasna Makovec
1983-01-01
Full Text Available Die vorliegende Arbeit wurde durch das Bestreben motiviert, weitere Ergänzungen zum Phänornen "Ausrahrnung in der modernen deutschen Schriftsprache der Gegenwart" zu leisten. Der Ausgangspunkt dieses "fakultativ" geregelten Bereiches ist die Annahme bzw. die Arbeitshypothese, daß sich linguistische und außerlinguistische Faktoren einander zuordnen lassen. Das bedeutet, daß die Linearität innerhalb des Kornrnunikationspro zesses auch einige wichtige kommunikative Funktionen auszuüben hat, und daß die kontextuellen Modifikationen der Stellungsva rianten bei gleichern Denotatsbezug unter diesern Blickwinkel untersucht werden müssen, und nicht gleich als stilistische Varianten qualifiziert werden.
Verbesserung der Symmetrie von Hirnaufnahmen entlang der Sagittalebene
Ens, Konstantin; Wenzel, Fabian; Fischer, Bernd
Die lokale Symmetrie von Hirnscans entlang der Sagittalebene zu ermitteln und zu modizifieren, ist für eine Reihe neurologischer Anwendungen interessant. Beispielsweise kann der voxelweise Vergleich von rechter und linker Hirnhälfte nur dann Aufschluss über die Lokalisierung von Läsionen geben, wenn durch Transformation ein Hirnscan eine möglichst hohe Symmetrie aufweist. Ein weiteres Anwendungsgebiet ist die Visualisierung von medialen Hirnschnitten, für die die Trennfläche beider Hirnhälfte möglichst eben sein sollte. Diese Arbeit stellt die Entwicklung eines Verfahrens vor, mit dessen Hilfe die Symmetrie von Hirnaufnahmen entlang der Sagittalebene verbessert werden kann. Dies geschieht unter Verwendung von aktiven Konturen, die mit Hilfe einer neuartigen Kostenfunktion gesteuert werden. Experimente am Ende der Arbeit mit strukturellen Kernspinaufnahmen demonstrieren die Leistungsfähigkeit des Verfahrens.
Coulomb interactions in charged fluids.
Vernizzi, Graziano; Guerrero-García, Guillermo Iván; de la Cruz, Monica Olvera
2011-07-01
The use of Ewald summation schemes for calculating long-range Coulomb interactions, originally applied to ionic crystalline solids, is a very common practice in molecular simulations of charged fluids at present. Such a choice imposes an artificial periodicity which is generally absent in the liquid state. In this paper we propose a simple analytical O(N(2)) method which is based on Gauss's law for computing exactly the Coulomb interaction between charged particles in a simulation box, when it is averaged over all possible orientations of a surrounding infinite lattice. This method mitigates the periodicity typical of crystalline systems and it is suitable for numerical studies of ionic liquids, charged molecular fluids, and colloidal systems with Monte Carlo and molecular dynamics simulations.
Der Heilige Geist und die Realisierung des Glaubens in der ...
African Journals Online (AJOL)
29. Juli 2016 ... der Sprache bis hin zu den kulturellen und religiösen. Zeichensystemen, muss von dem Einzelnen empfangen und angeeignet werden. Kommunikation, auch die religiöse, verwirklicht sich ausschließlich in der Spannung von geschichtlicher Abhängigkeit und Transformation der überlieferten Gehalte im ...
Directory of Open Access Journals (Sweden)
Radinković Željko
2012-01-01
Full Text Available (nemački Heideggersche erste Bewegungen in Richtung auf die Fundamentalontologie lassen sich in seinen Vorlesungen der frühen 20er Jahren beobachten. Heidegger versucht darin, sich von dem Logizismus der Husserlschen Bewusstseinsphilosophie zu emanzipieren, indem er ein Konzept der Urwissenschaft entwirft. Die Urwissenschaft soll bei der vortheoretischen Erfahrung, d. h. bei den vorreflexiven Erlebnissen ansetzen. Sie hat der entlebenden Tendenz der theoretischen Einstellung zum Erlebnisstrom entgegenzuwirken und somit die Voraussetzungen dafür zu schaffen, eine Vielfalt der lebendigen Erfahrungsweisen zum ausdrücklichen Verstehen zu bringen. Somit knüpft die Urwissenschaft an das Programm der Phänomenologie von Edmund Husserl, modifiziert es aber entscheidend, indem es aus der Sphäre des Bewusstseins in jene des lebendigen Erlebnisstroms verlegt.
Monotonicity of energy eigenvalues for Coulomb systems
International Nuclear Information System (INIS)
Englisch, R.
1983-01-01
Generalising results by earlier workers for a large class of Hamiltonians (among others, Hamiltonians of Coulomb systems) which can be written in the form H(α) = H 0 + αH' the present works shows that their eigenvalues decrease with increasing α. This result is applied to Coulomb systems in which the distances between the infinitely heavy particles are varying and also is used to obtain a completion and simplification of proof for the stability of the biexciton. (author)
International Nuclear Information System (INIS)
Krasnikov, N.V.
1987-01-01
Nonlocal gauge theories including gravity are considered. It is shown that the introduction of the additional nonlocal interaction makes γ 5 -anomalous theories meaningful. The introduction of such interaction leads to macrocausal unitary theory, which describes the interaction of massive vector fields with fermion fields. It is shown that nonlocal gauge theories with nonlocal scale Λ nl ≤(1-10) TeV can solve the gauge hierarchy problem. An example of nonlinear grand unified gauge model in which topologically nontrivial finite energy monopole solutions are absent is found
Critical opalescence in the pure Coulomb system
International Nuclear Information System (INIS)
Bobrov, V.B.; Trigger, S.A.
2011-01-01
Highlights: → The review of the critical opalescence problem is presented. → Light scattering in a two-component electron-nuclear system is studied. → The exact relations between the structure factors and compressibility are found. → The obtained relations are valid for strong interaction for the Coulomb systems. → The experimental verification of these relations is possible for various elements. - Abstract: Based on the dielectric formalism and quantum field theory methods, the phenomenon of critical opalescence is explained for light scattering in pure matter as a two-component electron-nuclear system with Coulomb interaction. A similar phenomenon is shown to occur in the case of neutron scattering in pure substances as well. The obtained results are valid for quantum case and arbitrary strong Coulomb interaction. Thus, the relations between structure factors derived for the electron-nuclear system are the exact result of the quantum statistical mechanics.
IFRS 8 OPERATING SEGMENTS: Eine Untersuchung der erstmaligen Anwendung in der Schweiz
Meyer, C; Weiss, S
2010-01-01
Seit dem 1. Januar 2009 sind kotierte IFRS-Anwender verpflichtet, eine Segmentberichterstattung nach IFRS 8 zu erstellen. Anhand einer Analyse der Geschäftsberichte 2009 der an der SIX Swiss Exchange kotierten Unternehmen soll ein Überblick über die erstmalige Anwendung von IFRS 8 "Operating Segments" in der Schweiz gewonnen werden.
Hat das humane Wachtumshormon (hGH eine Relevanz in der Kontrolle der penilen Erektion?
Directory of Open Access Journals (Sweden)
Ückert St
2003-01-01
Full Text Available Allgemeines: Schon seit langem wird die Frage einer Beteiligung des Hypophysenhormons Human Growth Hormone (Wachstumshormon, hGH, GH an der Kontrolle der sexuellen Maturation und der Reproduktionsfunktion des Menschen diskutiert. Die Symptome eines GH-Defizits beim Mann sind u. a. allgemeine Antriebslosigkeit, Oligo- oder Azoospermie, eine Verminderung der Libido sowie eine Beeinträchtigung der normalen Erektionsfähigkeit. Es wird vermutet, daß die biologischen Effekte des GH eine durch das Somatomedin Insulin-like Growth Factor 1 (IGF-1 vermittelte Stimulation der Produktion von Stickoxid (NO durch die endotheliale und neuronale Form des Enzyms NO-Synthase einschließen. So konnte gezeigt werden, daß physiologische Konzentrationen von GH den adrenergen Tonus isolierter Streifenpräparate humaner Schwellkörpermuskulatur antagonisieren und den Gewebegehalt des Second Messengers cGMP erhöhen. Im Rahmen dieser Studie haben wir in einem Kollektiv gesunder Männer und in einer Gruppe von Patienten mit erektiler Dysfunktion (ED die systemischen und cavernösen Serumkonzentrationen von GH während verschiedener peniler Funktionszustände, d. h. verschiedener Stadien der sexuellen Erregung, untersucht. Methoden: 35 gesunden männlichen Probanden und 45 Patienten mit einer ED organogener oder psychogener Genese wurden während der penilen Flakzidität, Tumeszenz, Rigidität - dieses Stadium wurde nur von den Gesunden erreicht - und Detumeszenz zeitgleich Blutproben aus einer Cubitalvene und dem Corpus cavernosum penis entnommen. Tumeszenz und Rigidität wurden durch visuelle und taktile Stimulation ausgelöst. Die Quantifizierung von GH in Aliquots der Serumfraktionen erfolgte mit immunradiometrischen Methoden (IRMA. Ergebnisse: In der Gruppe der gesunden Männer stieg die mittlere systemische und cavernöse Serumkonzentration von GH während der Tumeszenz an, während in den Phasen der Rigidität und Detumeszenz eine Abnahme registriert wurde
4-center STO interelectron repulsion integrals with Coulomb Sturmians
DEFF Research Database (Denmark)
Avery, James Emil; Avery, John Scales
2018-01-01
Abstract We present a method for evaluating 4-center electron repulsion integrals (ERI) for Slater-type orbitals by way of expansions in terms of Coulomb Sturmians. The ERIs can then be evaluated using our previously published methods for rapid evaluation of Coulomb Sturmians through hyperspherical...
Effizienz der Rebiopsie der Prostata: Untersuchungen von Transitionalzonen- und lateralen Biopsien
Directory of Open Access Journals (Sweden)
Fink KG
2003-01-01
Full Text Available Zweck dieser Untersuchung war es, die Effizienz von Transitionalzonenbiopsien und von Biopsien der lateralen Anteile der Prostata zur Karzinomentdeckung zu untersuchen, nachdem eine vorangegangene Biopsie keinen Tumor finden konnte. Methodik: Wir untersuchten 74 Präparate nach radikaler Prostatektomie und unterzogen diese einer sonographisch gezielten Prostatabiopsie ex vivo. Zuerst erfolgte eine Sextantenbiopsie, dann zwei unterschiedliche Rebiopsien. Rebiopsie-Technik A bestand aus einer lateral plazierten Sextantenbiopsie und zwei Stanzen aus den Transitionalzonen je Seite. Rebiopsie-Technik B bestand aus einer Sextantenbiopsie und zwei Stanzen je Seite aus den lateralen Arealen der Prostata. Ergebnisse: Mit der initialen Sextantenbiopsie konnten 39 Karzinome gefunden werden (53 %. Von den verbliebenen Karzinomen konnten mit der Rebiopsie-Technik A 12 Karzinome gefunden werden. In dieser Gruppe fand eine lateral durchgeführte Sextantenbiopsie 12 Karzinome. Die Transitionalzonenbiopsien waren in 5 Fällen positiv, jedoch konnte kein zusätzlicher Tumor entdeckt werden. Mit der Rebiopsie-Technik B wurden 23 Karzinome gefunden. 14 Tumore enthielten die Stanzen der Sextantenbiopsie. Zusätzliche 9 Tumore waren in den Stanzen aus den lateralen Arealen der Prostata enthalten. Schlußfolgerungen: Eine Standard-Sextantenbiopsie hat eine niedrige Sensitivität von nur 53 %. Eine Biopsie, welche die Transitionalzonen inkludiert, ist nicht geeignet, die verbliebenen Karzinome zu finden. In dieser Studie zeigte die Wiederholung einer Sextantenbiopsie mit zusätzlichen Stanzen aus den lateralen Arealen das beste Ergebnis bei der Rebiopsie.
Controllability of the Coulomb charging energy in close-packed nanoparticle arrays.
Duan, Chao; Wang, Ying; Sun, Jinling; Guan, Changrong; Grunder, Sergio; Mayor, Marcel; Peng, Lianmao; Liao, Jianhui
2013-11-07
We studied the electronic transport properties of metal nanoparticle arrays, particularly focused on the Coulomb charging energy. By comparison, we confirmed that it is more reasonable to estimate the Coulomb charging energy using the activation energy from the temperature-dependent zero-voltage conductance. Based on this, we systematically and comprehensively investigated the parameters that could be used to tune the Coulomb charging energy in nanoparticle arrays. We found that four parameters, including the particle core size, the inter-particle distance, the nearest neighboring number, and the dielectric constant of ligand molecules, could significantly tune the Coulomb charging energy.
Der Begriff der Verständlichkeit in der modernen Physik (1948).
Feyerabend, Paul K
2016-06-01
This is a critical transcription of Paul Feyerabend's earliest extant essay "Der Begriff der Verständlichkeit in der modernen Physik" (1948) recovered from the European Forum Alpbach archives. In it, Feyerabend defends positivism as a progressive framework for scientific research in certain stages of scientific development. He argues that in physics visualizability (Anschaulichkeit) and intelligibility (Verständlichkeit) are time-conditioned concepts: what is deemed visualizable in the development of physical theories is relative to a specific historical context and changes over time. He concludes that from time to time the abandonment of visualizability is crucial for progress in physics, as it is conducive to major theory change, illustrating the point on the basis of advances in atomic theory. Copyright © 2015 Elsevier Ltd. All rights reserved.
Directory of Open Access Journals (Sweden)
Sostmann, Kai
2009-02-01
Full Text Available Der studentische Unterricht in der Kinderheilkunde an der Charité hat seit 1999 mehrere Umstrukturierungen durchlaufen. Mit der Einführung der neuen ärztlichen Approbationsordnung 2004 im Regelstudiengang (RSG und dem Modellcurriculum Reformstudiengang Medizin (RSM 1999 müssen zwei Curricula parallel neu konzipiert und gepflegt werden. Durch den Schwerpunkt Unterricht am Krankenbett (UaK im RSG ergaben sich neue didaktische, pädagogische und infrastrukturelle Anforderungen. Die technische und inhaltliche Weiterentwicklung der Einsatzmöglichkeiten elektronischer Lernszenarien durch e-Learning im Rahmen des BMBF-geförderten Projektes ELWIS-MED, ermöglichte die Erprobung der curricularen Implementierung von e-Learning-Modulen im Pflichtunterricht. Der UaK wurde durch die Bearbeitung kinderheilkundlicher elektronischer Lernfälle online ergänzt. Die Studierenden sollten tutoriell betreute Diskussionen zu fachlichen Aufgabenstellungen online führen. In der ersten Erprobungsstufe wurde der Einsatz der Diskussionsforen in Verbindung mit den Lernfällen von den Studierenden und Lehrenden als sinnvolle Ergänzung betrachtet. In zukünftigen Einsatzszenarien sollte eine Messung des studentischen Lernerfolgs mit dieser Methode erfolgen.
Metal nanoparticle film-based room temperature Coulomb transistor.
Willing, Svenja; Lehmann, Hauke; Volkmann, Mirjam; Klinke, Christian
2017-07-01
Single-electron transistors would represent an approach to developing less power-consuming microelectronic devices if room temperature operation and industry-compatible fabrication were possible. We present a concept based on stripes of small, self-assembled, colloidal, metal nanoparticles on a back-gate device architecture, which leads to well-defined and well-controllable transistor characteristics. This Coulomb transistor has three main advantages. By using the scalable Langmuir-Blodgett method, we combine high-quality chemically synthesized metal nanoparticles with standard lithography techniques. The resulting transistors show on/off ratios above 90%, reliable and sinusoidal Coulomb oscillations, and room temperature operation. Furthermore, this concept allows for versatile tuning of the device properties such as Coulomb energy gap and threshold voltage, as well as period, position, and strength of the oscillations.
Implantate in der Augenheilkunde
Dresp, Joachim H.
Im Bereich der Augenheilkunde findet sich die weltweit am häufigsten ausgeführte chirurgische Massnahme, die operative Behandlung des Grauen Stars: die Katarakt. Bei der Katarakt handelt es sich um eine Eintrübung der natürlichen Augenlinse, die sich je nach Stadium der Erkrankung leicht opak, über milchig bis zu bräunlich präsentiert. Mit dieser Zunahme der Undurchlässigkeit für das sichtbare Licht geht eine Abnahme des Sehvermögens einher, die bis zur totalen Erblindung führen kann. Bedingt durch die sehr eingeschränkten chirurgischen Möglichkeiten in den Ländern der Dritten Welt ist die Katarakt die Erblindungsursache Nummer 1 in der Welt. Ganz im Gegensatz hierzu ist in den industrialisierten Ländern Europas, Amerikas und Asiens die Katarakt-OP die sicherste chirurgische Intervention. In der Augenheilkunde werden Implantate aller drei Aggregatszustände verwendet.
International Nuclear Information System (INIS)
Lin, C.Y.; Ho, Y.K.
2010-01-01
The screening effects due to the exponential-cosine-screened Coulomb and screened Coulomb (Yukawa) potentials on photoionization processes are explored within the framework of complex coordinate rotation method. The energy levels of H and He + in both screened potentials shifted with various Debye screening lengths are presented. The photoionization cross sections illustrate the considerable screening effects on photoionization processes in low energy region. The shape resonances can be found near ionization thresholds for certain of Debye screening lengths. The relations between the appearance of resonances and the existence of quasi-bound states under shielding conditions are discussed. (authors)
Vorkommen und Soziologie der Cuscuta-Arten in der Ufervegetation des Niederrheins
Schmitz, Ulf; Lösch, Rainer
2016-01-01
Um den Stand der gegenwärtigen Verbreitung der drei in der Ufervegetation des Niederrheins vorkommenden Cuscuta-Arten C. lupuliformis KROCKER, C. europaea L. und C. gronovii WILLD. festzustellen, wurde eine Kartierung beider Rheinufer zwischen Monheim-Baumberg (Kr. Mettmann) und der niederländischen Grenze durchgeführt. Cuscuta europaea und Cuscuta lupuliformis sind im gesamten Rheinverlauf häufig zu finden, wobei letztere Art die Prallufer des Rheins bevorzugt. Die seltenere Art Cuscuta gron...
Harada–Tsutsui gauge recovery procedure: From Abelian gauge anomalies to the Stueckelberg mechanism
International Nuclear Information System (INIS)
Lima, Gabriel Di Lemos Santiago
2014-01-01
Revisiting a path-integral procedure developed by Harada and Tsutsui for recovering gauge invariance from anomalous effective actions, it is shown that there are two ways to achieve gauge symmetry: one already presented by the authors, which is shown to preserve the anomaly in the sense of standard current conservation law, and another one which is anomaly-free, preserving current conservation. It is also shown that the application of the Harada–Tsutsui technique to other models which are not anomalous but do not exhibit gauge invariance allows the identification of the gauge invariant formulation of the Proca model, also done by the referred authors, with the Stueckelberg model, leading to the interpretation of the gauge invariant map as a generalization of the Stueckelberg mechanism. -- Highlights: • A gauge restoration technique from Abelian anomalous models is discussed. • It is shown that there is another way that leads to gauge symmetry restoration from such technique. • It is shown that the first gauge restoration preserves the anomaly, while the proposed second one is free from anomalies. • It is shown that the proposed gauge symmetry restoration can be identified with the Stueckelberg mechanism
Harada–Tsutsui gauge recovery procedure: From Abelian gauge anomalies to the Stueckelberg mechanism
Energy Technology Data Exchange (ETDEWEB)
Lima, Gabriel Di Lemos Santiago, E-mail: gabriellemos3@hotmail.com
2014-02-15
Revisiting a path-integral procedure developed by Harada and Tsutsui for recovering gauge invariance from anomalous effective actions, it is shown that there are two ways to achieve gauge symmetry: one already presented by the authors, which is shown to preserve the anomaly in the sense of standard current conservation law, and another one which is anomaly-free, preserving current conservation. It is also shown that the application of the Harada–Tsutsui technique to other models which are not anomalous but do not exhibit gauge invariance allows the identification of the gauge invariant formulation of the Proca model, also done by the referred authors, with the Stueckelberg model, leading to the interpretation of the gauge invariant map as a generalization of the Stueckelberg mechanism. -- Highlights: • A gauge restoration technique from Abelian anomalous models is discussed. • It is shown that there is another way that leads to gauge symmetry restoration from such technique. • It is shown that the first gauge restoration preserves the anomaly, while the proposed second one is free from anomalies. • It is shown that the proposed gauge symmetry restoration can be identified with the Stueckelberg mechanism.
Suchert, Anne
2015-01-01
Diese wissenschaftliche Arbeit beschäftigt sich mit der Eigentümlichkeit der geschriebenen Modesprache. Da die Modesprache offensichtliche sprachliche Auffälligkeiten sowie einen überaus kreativen und erfrischend humorvollen Umgang mit Sprache aufweist, sollte sie unter wissenschaftlichen Aspekten betrachtet werden. Mode ist eine Institution mit der sich die Soziologie seit jeher ausführlich beschäftigt. Somit stellt sie auch einen interessanten Untersuchungsgegenstand für die Soziolinguisti...
Quantum and classical gauge symmetries
International Nuclear Information System (INIS)
Fujikawa, Kazuo; Terashima, Hiroaki
2001-01-01
The use of the mass term of the gauge field as a gauge fixing term, which was discussed by Zwanziger, Parrinello and Jona-Lasinio in a large mass limit, is related to the non-linear gauge by Dirac and Nambu. We have recently shown that this use of the mass term as a gauge fixing term is in fact identical to the conventional local Faddeev-Popov formula without taking a large mass limit, if one takes into account the variation of the gauge field along the entire gauge orbit. This suggests that the classical massive vector theory, for example, could be re-interpreted as a gauge invariant theory with a gauge fixing term added in suitably quantized theory. As for massive gauge particles, the Higgs mechanics, where the mass term is gauge invariant, has a more intrinsic meaning. We comment on several implications of this observation. (author)
Known-to-Unknown Approach to Teach about Coulomb's Law
Thamburaj, P. K.
2007-01-01
Analogies from life experiences help students understand various relationships presented in an introductory chemistry course. Coulomb's law is a complex relationship encountered in introductory general chemistry. A proper understanding of the relationships between the quantities involved in Coulomb's law is necessary in order for students to…
Antilocalization of Coulomb Blockade in a Ge-Si Nanowire
DEFF Research Database (Denmark)
Higginbotham, Andrew P.; Kuemmeth, Ferdinand; Larsen, Thorvald Wadum
2014-01-01
The distribution of Coulomb blockade peak heights as a function of magnetic field is investigated experimentally in a Ge-Si nanowire quantum dot. Strong spin-orbit coupling in this hole-gas system leads to antilocalization of Coulomb blockade peaks, consistent with theory. In particular, the peak...
McClarty, P. A.; O'Brien, A.; Pollmann, F.
2014-05-01
We consider a classical model of charges ±q on a pyrochlore lattice in the presence of long-range Coulomb interactions. This model first appeared in the early literature on charge order in magnetite [P. W. Anderson, Phys. Rev. 102, 1008 (1956), 10.1103/PhysRev.102.1008]. In the limit where the interactions become short ranged, the model has a ground state with an extensive entropy and dipolar charge-charge correlations. When long-range interactions are introduced, the exact degeneracy is broken. We study the thermodynamics of the model and show the presence of a correlated charge liquid within a temperature window in which the physics is well described as a liquid of screened charged defects. The structure factor in this phase, which has smeared pinch points at the reciprocal lattice points, may be used to detect charge ice experimentally. In addition, the model exhibits fractionally charged excitations ±q/2 which are shown to interact via a 1/r potential. At lower temperatures, the model exhibits a transition to a long-range ordered phase. We are able to treat the Coulombic charge ice model and the dipolar spin ice model on an equal footing by mapping both to a constrained charge model on the diamond lattice. We find that states of the two ice models are related by a staggering field which is reflected in the energetics of these two models. From this perspective, we can understand the origin of the spin ice and charge ice ground states as coming from a dipolar model on a diamond lattice. We study the properties of charge ice in an external electric field, finding that the correlated liquid is robust to the presence of a field in contrast to the case of spin ice in a magnetic field. Finally, we comment on the transport properties of Coulombic charge ice in the correlated liquid phase.
Frictional Coulomb drag in strong magnetic fields
DEFF Research Database (Denmark)
Bønsager, Martin Christian; Flensberg, Karsten; Hu, Ben Yu-Kuang
1997-01-01
A treatment of frictional Coulomb drag between two two-dimensional electron layers in a strong perpendicular magnetic field, within the independent electron picture, is presented. Assuming fully resolved Landau levels, the linear response theory expression for the transresistivity rho(21) is eval......A treatment of frictional Coulomb drag between two two-dimensional electron layers in a strong perpendicular magnetic field, within the independent electron picture, is presented. Assuming fully resolved Landau levels, the linear response theory expression for the transresistivity rho(21...
Physics of the Non-Abelian Coulomb Phase
DEFF Research Database (Denmark)
Ryttov, Thomas A.; Shrock, Robert
2018-01-01
are applied to obtain further estimates of $\\gamma_{\\bar\\psi\\psi,IR}$ and $\\beta'_{IR}$ for several SU($N_c$) groups and representations $R$, and comparisons are made with lattice measurements. We apply our results to obtain new estimates of the extent of the respective non-Abelian Coulomb phases in several....... It is shown that an expansion of $\\gamma_{\\bar\\psi\\psi,IR}$ to $O(\\Delta_f^4)$ is quite accurate throughout the entire non-Abelian Coulomb phase of this supersymmetric theory....
Higher-order dynamical effects in Coulomb dissociation
International Nuclear Information System (INIS)
Esbensen, H.
1994-06-01
We study the effect of higher-order processes in Coulomb dissociation of 11 Li by numerically solving the three-dimensional time-dependent Schroedinger equation for the relative motion of a di-neutron and the 9 Li core. Comparisons are made to first-order perturbation theory and to measurements. The calculated Coulomb reacceleration effects improve the agreement with experiment, but some discrepancy remains. The effects are much smaller in the dissociation of 11 Be, and they decrease with increasing beam energy. (orig.)
Coulomb corrections to scattering length and effective radius
International Nuclear Information System (INIS)
Mur, V.D.; Kudryavtsev, A.E.; Popov, V.S.
1983-01-01
The problem considered is extraction of the ''purely nuclear'' scattering length asub(s) (corresponding to the strong potential Vsub(s) at the Coulomb interaction switched off) from the Coulomb-nuclear scattering length asub(cs), which is an object of experimental measurement. The difference between asub(s) and asub(cs) is especially large if the potential Vsub(s) has a level (real or virtual) with an energy close to zero. For this case formulae are obtained relating the scattering lengths asub(s) and asub(cs), as well as the effective radii rsub(s) and rsub(cs). The results are extended to states with arbitrary angular momenta l. It is shown that the Coulomb correction is especially large for the coefficient with ksup(2l) in the expansion of the effective radius; in this case the correction contains a large logarithm ln(asub(B)/rsub(0)). The Coulomb renormalization of other terms in the effective radius espansion is of order (rsub(0)/asub(B)), where r 0 is the nuclear force radius, asub(B) is the Bohr radius. The obtained formulae are tried on a number of model potentials Vsub(s), used in nuclear physics
Topologically massive gauge theories and their dual factorized gauge-invariant formulation
International Nuclear Information System (INIS)
Bertrand, Bruno; Govaerts, Jan
2007-01-01
There exists a well-known duality between the Maxwell-Chern-Simons theory and the 'self-dual' massive model in (2 + 1) dimensions. This dual description may be extended to topologically massive gauge theories (TMGT) for forms of arbitrary rank and in any dimension. This communication introduces the construction of this type of duality through a reparametrization of the 'master' theory action. The dual action thereby obtained preserves the full gauge symmetry structure of the original theory. Furthermore, the dual action is factorized into a propagating sector of massive gauge-invariant variables and a decoupled sector of gauge-variant variables defining a pure topological field theory. Combining the results obtained within the Lagrangian and Hamiltonian formulations, a completed structure for a gauge-invariant dual factorization of TMGT is thus achieved. (fast track communication)
Coulomb Logarithm in Nonideal and Degenerate Plasmas
Filippov, A. V.; Starostin, A. N.; Gryaznov, V. K.
2018-03-01
Various methods for determining the Coulomb logarithm in the kinetic theory of transport and various variants of the choice of the plasma screening constant, taking into account and disregarding the contribution of the ion component and the boundary value of the electron wavevector are considered. The correlation of ions is taken into account using the Ornstein-Zernike integral equation in the hypernetted-chain approximation. It is found that the effect of ion correlation in a nondegenerate plasma is weak, while in a degenerate plasma, this effect must be taken into account when screening is determined by the electron component alone. The calculated values of the electrical conductivity of a hydrogen plasma are compared with the values determined experimentally in the megabar pressure range. It is shown that the values of the Coulomb logarithm can indeed be smaller than unity. Special experiments are proposed for a more exact determination of the Coulomb logarithm in a magnetic field for extremely high pressures, for which electron scattering by ions prevails.
Global aspects of gauge anomalies
International Nuclear Information System (INIS)
Zhang, H.
1988-01-01
This dissertation discusses the global aspects of gauge anomalies in even dimensions. After a very brief description of local gauge anomalies, the possible global gauge anomalies for various gauge theories are discussed using homotopy theory. One of the main results obtained in a general formula for the SU(n - k) global gauge anomaly coefficient in arbitrary 2n dimensions. The result is expressed in terms of the James number of the Stiefel manifold SU(n + 1)/SU(n - k) and the generalized Dynkin indices. From this, the possibilities of SU(n), SU(n - 1), and SU(2) global gauge anomalies in arbitrary 2n dimensions have been determined. We have also determined the possibilities of global gauge anomalies for the gauge groups SP(2N) and SO(N) in certain general dimensions, as well as for the exceptional gauge groups in specific dimensions. Moreover, several general propositions are formulated and proved which are very useful in the study of global gauge anomalies
Coulomb corrections to nuclear scattering lengths and effective ranges for weakly bound systems
International Nuclear Information System (INIS)
Mur, V.D.; Popov, V.S.; Sergeev, A.V.
1996-01-01
A procedure is considered for extracting the purely nuclear scattering length as and effective range rs (which correspond to a strong-interaction potential Vs with disregarded Coulomb interaction) from the experimentally determined nuclear quantities acs and rcs, which are modified by Coulomb interaction. The Coulomb renormalization of as and rs is especially strong if the system under study involves a level with energy close to zero (on the nuclear scale). This applies to formulas that determine the Coulomb renormalization of the low-energy parameters of s scattering (l=0). Detailed numerical calculations are performed for coefficients appearing in the equations that determine Coulomb corrections for various models of the potential Vs(r). This makes it possible to draw qualitative conclusions that the dependence of Coulomb corrections on the form of the strong-interaction potential and, in particular, on its small-distance behavior. A considerable enhancement of Coulomb corrections to the effective range rs is found for potentials with a barrier
Considerações gerais sôbre os biótopos e habitats dos Anofelíneos do sub-gênero Kerteszia
Directory of Open Access Journals (Sweden)
Henrique P. Veloso
1958-07-01
Full Text Available Die vorliegende Arbiet koennen wir, entsprechend den obigen Erklaerungen, wie folgt, zusammenfassen: 1. Es bestehen im vertikalen Sinne besondere oekologische Bedingungen bezueglich der Eiablage fuer Anopheles (Kerteszia homunculus und bellator, waehrend A. (K. cruzii eine grosse Indifferenz bezueglich des Mikroklimas zeigt. 2. Die Anophelinen zeigen keine besondere Bevorzugung irgendeiner Bromelienart in Bezug auf die Eiablage. Es laesst sich feststellen, dass gewisse Bedingungen eines Biotops erfuelt sein muessen, damit dieses in begrenztem Wohnbezirk zu ienem ausgesprochenen Brutplatz wird. Aus diesem Grunde wurden einige Bromelienarten zu Hauptbrutstaetten der Anopheleslarven des Gebietes. 3. Bezueglich der Wassermenge finden wir in der gesamten Region die Anopheleslarven weitaus am haeufigsten in Bromelien mit grosser Kapazitaet. Die Arten mit geringem Fassungsvermoegen, die wesentlich zahlreicher als die erstgenannten sind, sind nur gute Brutstaetten, ween sie auf dem Boden wachsen oder Talsohle in huegeligem Gelaende, dort wo der Wald ausreichend dicht ist. Hier halten die mikroklimatischen Bedingungen die Verdunstung hintan, wodurch den Anopheleslarven in diesen Bromelien das Leben ermoeglicht wird. 4. Es besteht eine Beziehung zwischen der Periodizitaet der Larven und der gefluegelten Formen der Anophelinen, die in einem Waldstueck gefangen wurden. Die letzteren zeigen im vertikalen Sinne keine ausgesprochenen Variationen bezueglich der prozentualen Haeufigkeit, waehrend die Larven in ieder Hoehe ausgesprochene Haeufigkeitsschwankungen aufweisen, die immer von der von Art bevorzugten Habitat in einer bestimmten Hoehenlage abhaengen. Bezueglich einer moeglichst vollstaendigen Erklaerung des Problems "Bromelien-Malaria" dieser Region, koennen wir folgendes feststellen: 5. Die definitive Loesung des Problems wird wesentlich erleichtert durch den Nachweis, dass nur eine geringe Anzahl von Bromelien (12 Arten - und gerate die weniger
Gauge symmetry from decoupling
Directory of Open Access Journals (Sweden)
C. Wetterich
2017-02-01
Full Text Available Gauge symmetries emerge from a redundant description of the effective action for light degrees of freedom after the decoupling of heavy modes. This redundant description avoids the use of explicit constraints in configuration space. For non-linear constraints the gauge symmetries are non-linear. In a quantum field theory setting the gauge symmetries are local and can describe Yang–Mills theories or quantum gravity. We formulate gauge invariant fields that correspond to the non-linear light degrees of freedom. In the context of functional renormalization gauge symmetries can emerge if the flow generates or preserves large mass-like terms for the heavy degrees of freedom. They correspond to a particular form of gauge fixing terms in quantum field theories.
DEFF Research Database (Denmark)
Decker-Phillips, Edith; Lemke, Inga; Bruns, Karin
¨ sterreich und der Schweiz, die seit Mitte der 1980er Jahre entstanden sind und den Begriff des Mediums Video bestimmen, erweitern, die spezifische Leistung der Videokunst deuten oder ihre Systematik und Historisierung versuchen. Es finden Texte Ber¨ ucksichtigung, die den sich ver¨andernden Gebrauch des...
Coulomb collisions in the solar wind
Klein, L. W.; Ogilvie, K. W.; Burlaga, L. F.
1985-01-01
A major improvement of the present investigation over previous studies of the subject is related to the use of helium temperatures obtained from helium ion measurements uncontaminated by the high-velocity tail of the proton distribution. More observations, covering a large parameter range, were employed, and the effects of interspecies drift were taken into account. It is shown in a more definite way than has been done previously, that Coulomb collisions provide the most important mechanism bringing about equilibrium between helium and protons in the solar wind. Other mechanisms may play some part in restricted regions, but Coulomb collisions are dominant on the macroscale.
Stereotactic core biopsy: Comparison of 11 gauge with 8 gauge vacuum assisted breast biopsy
Energy Technology Data Exchange (ETDEWEB)
Venkataraman, Shambhavi, E-mail: svenkata@bidmc.harvard.edu [Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215 (United States); Dialani, Vandana [Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215 (United States); Gilmore, Hannah L. [Department of Pathology, UH Case Medical Center, 11100 Euclid Ave, Cleveland, OH 44106 (United States); Mehta, Tejas S. [Department of Radiology, Beth Israel Deaconess Medical Center, 330 Brookline Avenue, Boston, MA 02215 (United States)
2012-10-15
Purpose: The compare the performance and ability to obtain a correct diagnosis on needle biopsy between 11 gauge and 8 gauge vacuum assisted biopsy devices. Materials and methods: Hospital records of all consecutive stereotactic core biopsies performed over five years were retrospectively reviewed in compliance Health Insurance Portability and Accountability Act (HIPPA) policy and with approval from the hospital institutional review board (IRB). Pathology from core biopsy was compared with surgical pathology and/or imaging follow-up. A histological underestimation was defined if the surgical excision yielded a higher grade on pathology which changed management. Results: 828 needle core biopsies (47.5%, 393/828 with 11 gauge and 52.5%, 435/828 with 8 gauge) yielded 471 benign, 153 high risk and 204 malignant lesions. 30/193 (15.5%) 11 gauge lesions and 16/185 (8.6%) 8 gauge lesions demonstrated higher grade pathology on surgical excision. The difference in the rates of the number of correct diagnoses on core needle biopsy between 11 gauge (363/393, 92.4%) and 8 gauge (419/435, 96.3%) based on either surgical or clinical/imaging follow up and the difference in the number of discordant benign core biopsies between 11 (17/217, 7.8%) and 8 gauge (4/254, 1.6%) necessitating a surgical biopsy was significant (P = 0.013; P = 0.001). Although there were more underestimations with the 11 gauge (25/193, 13.0%) than 8 gauge (15/185, 8.1%) needle, this was not significant. Conclusion: Our study demonstrates improved performance and increased diagnostic ability of 8 gauge needle over 11 gauge in obtaining a correct diagnosis on needle biopsy.
Extended pure Yang-Mills gauge theories with scalar and tensor gauge fields
International Nuclear Information System (INIS)
Gabrielli, E.
1991-01-01
The usual abelian gauge theory is extended to an interacting Yang-Mills-like theory containing vector, scalar and tensor gauge fields. These gauge fields are seen as components along the Clifford algebra basis of a gauge vector-spinorial field. Scalar fields φ naturally coupled to vector and tensor fields have been found, leading to a natural φ 4 coupling in the lagrangian. The full expression of the lagrangian for the euclidean version of the theory is given. (orig.)
Fast Electron Repulsion Integrals for Molecular Coulomb Sturmians
DEFF Research Database (Denmark)
Avery, James Emil
2013-01-01
A new method is presented for calculating interelectron repulsion integrals for molecular Coulomb Sturmian basis sets. This makes use of an expansion of densities in terms of 2k-Sturmians, and the interelectron repulsion integrals are then calculated by a method based on the theory of hyperspheri......A new method is presented for calculating interelectron repulsion integrals for molecular Coulomb Sturmian basis sets. This makes use of an expansion of densities in terms of 2k-Sturmians, and the interelectron repulsion integrals are then calculated by a method based on the theory...... of hyperspherical harmonics. A rudimentary software library has been implemented and preliminary benchmarks indicate very good performance: On average 40 ns, or approximately 80 clock cycles, per electron repulsion integral. This makes molecular Coulomb Sturmians competitive with Gaussian type orbitals in terms...
Metal nanoparticle film–based room temperature Coulomb transistor
Willing, Svenja; Lehmann, Hauke; Volkmann, Mirjam; Klinke, Christian
2017-01-01
Single-electron transistors would represent an approach to developing less power–consuming microelectronic devices if room temperature operation and industry-compatible fabrication were possible. We present a concept based on stripes of small, self-assembled, colloidal, metal nanoparticles on a back-gate device architecture, which leads to well-defined and well-controllable transistor characteristics. This Coulomb transistor has three main advantages. By using the scalable Langmuir-Blodgett method, we combine high-quality chemically synthesized metal nanoparticles with standard lithography techniques. The resulting transistors show on/off ratios above 90%, reliable and sinusoidal Coulomb oscillations, and room temperature operation. Furthermore, this concept allows for versatile tuning of the device properties such as Coulomb energy gap and threshold voltage, as well as period, position, and strength of the oscillations. PMID:28740864
Critical opalescence in the pure Coulomb system
Bobrov, V. B.; Trigger, S. A.
2011-04-01
Based on the dielectric formalism and quantum field theory methods, the phenomenon of critical opalescence is explained for light scattering in pure matter as a two-component electron-nuclear system with Coulomb interaction. A similar phenomenon is shown to occur in the case of neutron scattering in pure substances as well. The obtained results are valid for quantum case and arbitrary strong Coulomb interaction. Thus, the relations between structure factors derived for the electron-nuclear system are the exact result of the quantum statistical mechanics.
Exact solution of the N-dimensional generalized Dirac-Coulomb equation
International Nuclear Information System (INIS)
Tutik, R.S.
1992-01-01
An exact solution to the bound state problem for the N-dimensional generalized Dirac-Coulomb equation, whose potential contains both the Lorentz-vector and Lorentz-scalar terms of the Coulomb form, is obtained. 24 refs. (author)
Samartzis, E P; Imesch, P; Fink, D
2012-01-01
Ein grundlegendes Verständnis der Pathogenese der Endometriose ist eine zwingende Voraussetzung zur Etablierung neuer und wirksamer Therapieoptionen. Dabei erscheint die Endometriose als heterogene Gruppe von Krankheitsformen, die sich unterschiedlich manifestieren. Dies erklärt, weshalb die genaue Pathogenese der Endometriose bis heute ein nicht abschliessend erforschtes Gebiet bleibt.
Coulomb dissociation of 8B at 254 MeV/u
International Nuclear Information System (INIS)
Surowka, G.; Iwasa, N.; Boue, F.
1999-01-01
As an alternative method to determine the cross section of 7 Be (p, γ) 8 B, the Coulomb dissociation reaction 8 B → 7 Be + p at E inc = 254 MeV/u was measured. Our preliminary results show the dominant role of the dipole excitation in the Coulomb break-up process. The extracted astrophysical S 17 factor is consistent with the lower-value results both of the direct-capture studies, and the RIKEN Coulomb-dissociation experiment at ∼ 50 MeV/u. (author)
Dungl, Eva
2003-01-01
Seminararbeit im Rahmen des Seminars Globalisierung und Philosophie im WS 2003/2004 bei Univ.-Prof.Dr.Franz Martin Wimmer Inhalt:EINLEITUNG I.Infragestellen der Ökonomie als Wohlfahrt des Menschen II.Einbindung der Ethik in die Ökonomie III.Ist die Einbindung der Ethik in die Ökonomie möglich?IV.Versuch eines ontolologisch-erkenntnistheoretischen Ansatzes im Verhältnis Natur-Mensch I.Natur versus Technik HAUPTTEIL I.Natur versus Technik II.Der "Natur â€?-Begriff im a...
Energy Technology Data Exchange (ETDEWEB)
Jurčo, Branislav, E-mail: jurco@karlin.mff.cuni.cz [Charles University in Prague, Faculty of Mathematics and Physics, Mathematical Institute, Prague 186 75 (Czech Republic); Schupp, Peter, E-mail: p.schupp@jacobs-university.de [Jacobs University Bremen, 28759 Bremen (Germany); Vysoký, Jan, E-mail: vysokjan@fjfi.cvut.cz [Jacobs University Bremen, 28759 Bremen (Germany); Czech Technical University in Prague, Faculty of Nuclear Sciences and Physical Engineering, Prague 115 19 (Czech Republic)
2014-06-02
We generalize noncommutative gauge theory using Nambu–Poisson structures to obtain a new type of gauge theory with higher brackets and gauge fields. The approach is based on covariant coordinates and higher versions of the Seiberg–Witten map. We construct a covariant Nambu–Poisson gauge theory action, give its first order expansion in the Nambu–Poisson tensor and relate it to a Nambu–Poisson matrix model.
International Nuclear Information System (INIS)
Jurčo, Branislav; Schupp, Peter; Vysoký, Jan
2014-01-01
We generalize noncommutative gauge theory using Nambu–Poisson structures to obtain a new type of gauge theory with higher brackets and gauge fields. The approach is based on covariant coordinates and higher versions of the Seiberg–Witten map. We construct a covariant Nambu–Poisson gauge theory action, give its first order expansion in the Nambu–Poisson tensor and relate it to a Nambu–Poisson matrix model.
Indian Academy of Sciences (India)
University education was beyond reach for van der Waals as he had to work for earning his daily bread ... languages, which was a prerequisite for entering a University those days. van der Waals worked as a school ... take academic examinations at the University yet, van der Waals continued studying at Leiden. University ...
The generalized parabolic Coulomb wavefunction in spherical coordinates
Energy Technology Data Exchange (ETDEWEB)
Gasaneo, G. [Consejo Nacional de Investigaciones Cientificas y Tecnicas, Departamento de Fisica, Universidad del Sur, Buenos Aires (Argentina); Colavecchia, F.D.; Garibotti, C.R. [Consejo Nacional de Investigaciones Cientificas y Tecnicas, Centro Atomico Bariloche, Rio Negro (Argentina); Otranto, S. [Consejo Nacional de Investigaciones Cientificas y Tecnicas, Departamento de Fisica, Universidad del Sur, Buenos Aires (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas, Centro Atomico Bariloche, Rio Negro (Argentina)
2001-10-19
In this work we present a detailed study of the recently introduced {delta}{sub m,n} basis for three Coulomb particles. We show that the scattering and generalized Coulomb problems as well as a {phi}{sub 2} approach can be viewed as particular cases of this basis. We derive a partial wave expansion for {delta}{sub m,n} functions and analyse the reduction to some of the precedent cases. (author)
Coulomb excitation of radioactive 20, 21Na
Schumaker, M. A.; Cline, D.; Hackman, G.; Pearson, C.; Svensson, C. E.; Wu, C. Y.; Andreyev, A.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D.; Becker, J. A.; Boston, A. J.; Boston, H. C.; Buchmann, L.; Churchman, R.; Cifarelli, F.; Cooper, R. J.; Cross, D. S.; Dashdorj, D.; Demand, G. A.; Dimmock, M. R.; Drake, T. E.; Finlay, P.; Gallant, A. T.; Garrett, P. E.; Green, K. L.; Grint, A. N.; Grinyer, G. F.; Harkness, L. J.; Hayes, A. B.; Kanungo, R.; Lisetskiy, A. F.; Leach, K. G.; Lee, G.; Maharaj, R.; Martin, J.-P.; Moisan, F.; Morton, A. C.; Mythili, S.; Nelson, L.; Newman, O.; Nolan, P. J.; Orce, J. N.; Padilla-Rodal, E.; Phillips, A. A.; Porter-Peden, M.; Ressler, J. J.; Roy, R.; Ruiz, C.; Sarazin, F.; Scraggs, D. P.; Waddington, J. C.; Wan, J. M.; Whitbeck, A.; Williams, S. J.; Wong, J.
2009-12-01
The low-energy structures of the radioactive nuclei 20, 21Na have been examined using Coulomb excitation at the TRIUMF-ISAC radioactive ion beam facility. Beams of ˜ 5×106 ions/s were accelerated to 1.7MeV/A and Coulomb excited in a 0.5mg/cm^2 natTi target. Two TIGRESS HPGe clover detectors perpendicular to the beam axis were used for γ -ray detection, while scattered nuclei were observed by the Si detector BAMBINO. For 21Na , Coulomb excitation from the 3/2+ ground state to the first excited 5/2+ state was observed, while for 20Na , Coulomb excitation was observed from the 2+ ground state to the first excited 3+ and 4+ states. For both beams, B ( λ L) values were determined using the 2+ rightarrow 0+ de-excitation in 48Ti as a reference. The resulting B( E2) ↓ value for 21Na is 137±9 e^2fm^4, while the resulting B( λ L) ↓ values for 20Na are 55±6 e^2fm^4 for the 3+ rightarrow 2+ , 35.7±5.7 e^2 fm^4 for the 4+ rightarrow 2+ , and 0.154±0.030 μ_ N^2 for the 4+ rightarrow 3+ transitions. This analysis significantly improves the measurement of the 21Na B( E2) value, and provides the first experimental determination of B( λ L) values for the proton dripline nucleus 20Na .-1
Coulomb-gas scaling, superfluid films, and the XY model
International Nuclear Information System (INIS)
Minnhagen, P.; Nylen, M.
1985-01-01
Coulomb-gas-scaling ideas are invoked as a link between the superfluid density of two-dimensional 4 He films and the XY model; the Coulomb-gas-scaling function epsilon(X) is extracted from experiments and is compared with Monte Carlo simulations of the XY model. The agreement is found to be excellent
Kuhn, Wildfried
2016-01-01
Die Ideengeschichte der Physik geht neue Wege, indem sie den umfangreichen historischen Stoff nicht additiv darstellt, sondern wissenschaftstheoretisch reflektiert und nach thematischen Leitlinien (Materievorstellungen, Raum und Zeit, Erhaltungskonzepte, Extremalprinzipien, Theorie und Experiment) strukturiert. Damit vermittelt diese Darstellung im historischen Kontext ein tieferes Verständnis des physikalischen Denkens von der Antike bis heute und lotet zugleich die Dimension der Genesis physikalischer Begriffe aus, die in modernen Lehrbüchern zumeist nicht dargelegt wird. Das Credo Kuhns: Wer über die handwerkliche Handhabung von Physik hinausgehen will, muss sich zwingend mit der Frage befassen, was physikalisches Denken ausmacht und wie es entstanden ist. Die vorliegende zweite Auflage wurde ergänzt durch ein Vorwort von Prof. Dr. Oliver Schwarz, der im Institut Wilfried Kuhns forschen konnte und dabei dessen Denk- und Arbeitsweisen kennengelernt hat.
Urämische Kardiomyopathie und der Einfluss der Hämodialyse
Valina, Ulrike Katrin
2011-01-01
ZIEL: Analyse von Risikofaktoren und Entstehungsmechanismen der urämischen Kardiomyopathie bei Hämodialysepatienten und Vergleich von Diagnostiken zur frühen Detektion kardialer Funktionstörungen zur Optimierung der Therapie bei terminaler Niereninsuffizienz und Senkung der hohen Mortalitätsrate. METHODEN: Einschluss von 32 Hämodialysepatienten. Messungen mittels Blutentnahme (Entzündungs-, Atherosklerose-, Anämieparameter, EPO, PTH und RAAS) und MRT (Herzfunktion, Herzmorphologie und Her...
On the Emergence of the Coulomb Forces in Quantum Electrodynamics
Directory of Open Access Journals (Sweden)
Jan Naudts
2017-01-01
Full Text Available A simple transformation of field variables eliminates Coulomb forces from the theory of quantum electrodynamics. This suggests that Coulomb forces may be an emergent phenomenon rather than being fundamental. This possibility is investigated in the context of reducible quantum electrodynamics. It is shown that states exist which bind free photon and free electron fields. The binding energy peaks in the long-wavelength limit. This makes it plausible that Coulomb forces result from the interaction of the electron/positron field with long-wavelength transversely polarized photons.
Critical behavior in graphene with Coulomb interactions.
Wang, Jianhui; Fertig, H A; Murthy, Ganpathy
2010-05-07
We demonstrate that, in the presence of Coulomb interactions, electrons in graphene behave like a critical system, supporting power law correlations with interaction-dependent exponents. An asymptotic analysis shows that the origin of this behavior lies in particle-hole scattering, for which the Coulomb interaction induces anomalously close approaches. With increasing interaction strength the relevant power law changes from real to complex, leading to an unusual instability characterized by a complex-valued susceptibility in the thermodynamic limit. Measurable quantities, as well as the connection to classical two-dimensional systems, are discussed.
Directory of Open Access Journals (Sweden)
Henrique P. Veloso
1956-06-01
Full Text Available Die vorliegende Arbeit bildet einem Teil der Studien, die unter Leitung des nationalen Malaria-Dienstes in Zusammenarbeit mit Technikern des Institutes Oswaldo Cruz im Sueden Brasiliens durchgefuehrt werden und sich mit dem Problem des Wechselspiels zwischen Malaria und Bromeliacen befassen. Die verfasser bearbeiten in dieser Niederschrift, die den Anfang einer Serie ueber die erwaehnten Fragen darstellt, die Entwicklung der Anophelinen der Untergattung Kerteszia in den Wasseransammlungen der Blattwinkel von Bromelien. Es wurde das Munizip Brusque ausgewaehlt, da hier die Abhaengigkeit der Bevoelkerung vom Wald eine sehr enge ist und da dieses Gebiet fuer die Oekologie und Topographie der Suedregion charakteristisch ist. Den hier gefundenen Wald nennen die Autoren die “Suedbrasilianische Regenformation”. Vor der Ankunft der Arbeitsgruppe wurden die folgenden Methoden zur Bekaempfung der Brutstaetten der Malariauebertraeger angewendet: 1. Manuelle Entfernung der Bromelien aus den die Staedte umgebenden Waeldern, 2. Abholzung. Da diese beiden Methoden zu drastisch sind, benutzten die erwaehnten Techniker anfangs eine 0,5% ige Loesung von Kupfersulfat als “Bromelicid” und spaeter PariserGruen, das vom Flugzeug aus verstaeubt wurde. Um ueberfluessige Schaeden an den Pflanzengesellschaften zu vermeiden, wurde daran gedacht, auf Grund oekologischer Betrachtungen das Problem “Bromeliaceae-Malaria” nach dem Vorbild Pittendrigh’s in Trinidad zu loesen. Es wurde folgenden Arbeitsplan durchgefuehrt: 1. Studium der Vergesellchaftungen im Hinblick auf die Soziologie und ihre Beziehungen zu den Bromelien, 2. Auszaehlung der in den Bromelien enthaltenen Larven und Puppen, 3. Kenntnis des Mittelwertes der Larven, die sich zu Imagines entwickeln und 4. Mikrolima der Waelder usw. Die Oekologie der bromelien wurde in einer frueheren Publikation veroeffentlich (Veloso, H. P., 1952. Das botanische Material der vorliegenden Arbeit wurde von Spezialisten
Fiedler, Angelika Marion
2016-01-01
Im prospektiven Studienteil wurden Anwendbarkeit, Operationszeiten, Durchleuchtungseinsatz, Heilungsverlauf und Komplikationen bei der Versorgung von 25 Humerus-, Femur- und Tibiafrakturen der Katze mit dem MarMed Verriegelungsnagel(VN)-System untersucht. Die Röntgenbeurteilung fand durch 2 Beurteiler unabhängig voneinander statt. Zwischen den Beurteilern und den Wiederholungen der Knochenmessungen bestand eine sehr gute Übereinstimmung. Für Achsenabweichungen, Implantatsitz und Heilungsphase...
Resonance tuning due to Coulomb interaction in strong near-field coupled metamaterials
International Nuclear Information System (INIS)
Roy Chowdhury, Dibakar; Xu, Ningning; Zhang, Weili; Singh, Ranjan
2015-01-01
Coulomb's law is one of the most fundamental laws of physics that describes the electrostatic interaction between two like or unlike point charges. Here, we experimentally observe a strong effect of Coulomb interaction in tightly coupled terahertz metamaterials where the split-ring resonator dimers in a unit cell are coupled through their near fields across the capacitive split gaps. Using a simple analytical model, we evaluated the Coulomb parameter that switched its sign from negative to positive values indicating the transition in the nature of Coulomb force from being repulsive to attractive depending upon the near field coupling between the split ring resonators. Apart from showing interesting effects in the strong coupling regime between meta-atoms, Coulomb interaction also allows an additional degree of freedom to achieve frequency tunable dynamic metamaterials
Chemical potentials in gauge theories
International Nuclear Information System (INIS)
Actor, A.; Pennsylvania State Univ., Fogelsville
1985-01-01
One-loop calculations of the thermodynamic potential Ω are presented for temperature gauge and non-gauge theories. Prototypical formulae are derived which give Ω as a function of both (i) boson and/or fermion chemical potential, and in the case of gauge theories (ii) the thermal vacuum parameter Asub(O)=const (Asub(μ) is the euclidean gauge potential). From these basic abelian gauge theory formulae, the one-loop contribution to Ω can readily be constructed for Yang-Mills theories, and also for non-gauge theories. (orig.)
International Nuclear Information System (INIS)
Linauskas, S.H.
1988-08-01
Field studies to measure actual radiation exposures of operators of commercial moisture-density gauges were undertaken in several regions of Canada. Newly developed bubble detector dosimeter technology and conventional dosimetry such as thermoluminescent dosimeters (TLDs), integrating electronic dosimeters (DRDs), and CR-39 neutron track-etch detectors were used to estimate the doses received by 23 moisture-density gauge operators and maintenance staff. These radiation dose estimates were supported by mapping radiation fields and accounting for the time an operator was near a gauge. Major findings indicate that gauge maintenance and servicing workers were more likely than gauge operators to receive exposures above the level of 5 mSv, and that neutron doses were roughly the same as gamma doses. Gauge operators receive approximately 75% of their dose when transporting and carrying the gauge. Dose to their hands is similar to the dose to their trunks, but the dose to their feet area is 6 to 30 times higher. Gamma radiation is the primary source of radiation contributing to operator dose
Coulomb fission and transfer fission at heavy ion collisions
International Nuclear Information System (INIS)
Himmele, G.
1981-01-01
In the present thesis the first direct evidence of nuclear fission after inelastic scattering of heavy ions (sup(183,184)W, 152 Sm → 238 U; 184 W → 232 Th; 184 W, 232 Th → 248 Cm) is reported. Experiments which were performed at the UNILAC of the Gesellschaft fuer Schwerionenforschung in Darmstadt show the observed heavy ion induced fission possesses significant properties of the Coulomb fission. The observed dependence of the fission probability for inelastic scattering on the projectile charge proves that the nuclear fission is mediated by the electromagnetic interaction between heavy ions. This result suggests moreover a multiple Coulomb-excitation preceding the fission. Model calculations give a first indication, that the Coulomb fission proceeds mainly from the higher β phonons. In the irradiation with 184 W the fission probability of 232 Th is for all incident energies about 40% smaller that at 238 U. The target dependence of the Coulomb fission however doesn't allow, to give quantitative statements about the position and B(E2)-values of higher lying β phonons. (orig./HSI) [de
Directory of Open Access Journals (Sweden)
Ricarda Bolten
2018-03-01
Full Text Available Die Digitalisierung durchdringt die Lehr-/Lernprozesse in der Erwachsenenbildung immer stärker. Dadurch verändern sich die Anforderungen, denen Lehrende in der Erwachsenenbildung gegenüberstehen. Neben Änderungen der didaktischen Umsetzung des Lehr-/Lerninhalts denen die Lehrenden gegenüberstehen, müssen sie auf verschiedenen Ebenen medienbezogene Kompetenzen aufweisen, um medienpädagogisch kompetent zu handeln und damit den Anforderungen der Digitalisierung gerecht zu werden. Ohne breite medienpädagogische Kompetenzen können die Lehrenden ihren Aufgaben heutzutage nur schwer gerecht werden. In diesem Beitrag werden die, durch eine empirische Anforderungsanalyse identifizierten, Orientierungspunkte für die Gestaltung der medienpädagogischen Professionalisierung von Lehrenden beleuchtet. Hierzu werden die Ergebnisse einer qualitativen Interview- und Fokusgruppenuntersuchung mit Planenden/Einstellenden und Lehrenden in der Erwachsenenbildung vorgestellt. Diese Perspektivenverschränkung verschiedener Akteure der Erwachsenenbildung lässt erkennen, dass neben medienpädagogischen Kompetenzen auf Seiten der Lehrenden auch die organisationalen, äusseren Umstände in der Erwachsenenbildung den Medieneinsatz beeinflussen. Für ein zeitgemässes Weiterbildungssystem, in dem Lehrende digitale Medien kompetent und sinnstiftend einsetzen, müssen neben medienpädagogischen Kompetenzbeschreibungen auch die Anforderungen von (Weiterbildungs-Organisations- und Institutionsebenen transparenter erkennbar sein, um Lehrenden bei einer individuellen Professionalisierung Orientierungspunkte zu geben.
Wertigkeit der Schnittbilddiagnostik in der Evaluation des pädiatrischen Schädel-Hirn-Traumas
Schäffeler, Christoph
2010-01-01
Die vorliegende Arbeit untersucht die diagnostische Wertigkeit von Computertomographie (CT) und Magnetresonanztomographie (MRT) in der Diagnostik des pädiatrischen Schädel-Hirn-Traumas. In einer retrospektiven Auswertung der Bildgebung von 64 Patienten im Alter von 0-15 Jahren wurden die Vor- und Nachteile der CT und MRT - Diagnostik bei der Darstellung intrakranieller Traumfolgen herausgearbeitet. Die Ergebnisse räumen der CT weiterhin einen hohen Stellenwert in der Akutdiagnostik ein, zeige...
International Nuclear Information System (INIS)
Partovi, M.H.
1982-01-01
From a generalization of the covariant derivative, nonlocal gauge theories are developed. These theories enjoy local gauge invariance and associated Ward identities, a corresponding locally conserved current, and a locally conserved energy-momentum tensor, with the Ward identities implying the masslessness of the gauge field as in local theories. Their ultraviolet behavior allows the presence as well as the absence of the Adler-Bell-Jackiw anomaly, the latter in analogy with lattice theories
Kants Theorie der Sonne: Physikgeschichte
Jacobi, Manfred
2005-01-01
Im Rahmen seiner Kosmogonie entwickelte der junge Immanuel Kant eine Theorie der Sonne. Sie ist ein einzigartiges Zeugnis seiner intuitiven Vorstellungskraft und beweist auch die Leistungsfähigkeit der damaligen, vorwiegend von Newton geprägten Weltsicht. Entstehung, Aufbau und Dynamik der Sonne werden in Kants Theorie ebenso erklärt wie etwa das Phänomen der Sonnenflecken.
SU(2) gauge theory in the maximally Abelian gauge without monopoles
International Nuclear Information System (INIS)
Shmakov, S.Yu.; Zadorozhnyj, A.M.
1995-01-01
We present an algorithm for simulation of SU(2) lattice gauge theory under the maximally Abelian (MA) gauge and first numerical results for the theory without Abelian monopoles. The results support the idea that nonperturbative interaction arises between monopoles and residual Abelian field and the other interactions are perturbative. It is shown that the Gribov region for the theory with the MA gauge fixed is non-connected. 12 refs., 1 tab
Wrobel, Denise
2013-01-01
Einleitung: Die vorliegende Studie hatte das Ziel, die Effektivität der spezifischen Immuntherapie unter den imkernden Bienengiftallergikern und ihren Langzeitschutz zu belegen, wobei Sticherfahrungen der weiterimkernden Betroffenen herangezogen wurden, um die Wirksamkeit der Therapie zu bestätigen, sowie Veränderungen auf Verhalten und Psyche darzustellen. Inwiefern Imker eine "natürliche Immunisierung" durchführen und wie wirksam alternative Behandlungen sind, wurde ebenfalls untersucht. ...
Rekonstruktion mit Netz beim komplexen Prolaps der Frau: Was hilft es der Patientin wirklich?
Directory of Open Access Journals (Sweden)
Hierl J
2010-01-01
Full Text Available Einleitung: Der komplexe Genitaldeszensus der Frau geht oftmals mit einer deutlichen Einschränkung der Lebensqualität (LQ einher. Dennoch ist der Endpunkt der meisten klinischen Analysen rein anatomischer und funktioneller Natur. In der vorliegenden Untersuchung wurden die Einflüsse der operativen Rekonstruktion mit einem Netz prospektiv auf die LQ evaluiert. Patienten und Methoden: Bei insgesamt 111 Patientinnen mit Deszensus erfolgte zwischen 08/2005 und 12/2007 eine operative Versorgung mittels vaginaler Netzeinlage (anteriorer bzw. kompletter Mesh-Repair. Die LQ wurde prospektiv prä- und postoperativ anhand standardisierter LQ-Fragebögen erfasst. Ergebnisse: Präoperativ zeigte sich bei den Patientinnen eine signifikant reduzierte LQ gegenüber einem Normalkollektiv (p 0,01. Bei 7 % der Patientinnen mit anteriorem, und bei 11 % mit komplettem Mesh-Repair lag postoperativ kein adäquates klinisches Ergebnis vor. In diesem Kollektiv zeigte sich kein signifikanter Unterschied in den LQ-Tests prä- und postoperativ. Bei gutem postoperativem Ergebnis zeigte sich in der Gruppe mit anteriorer Netzeinlage lediglich bei 45 % (p = 0,021, bei kompletter Netzeinlage nur bei 31 % (p = 0,041 eine signifikant verbesserte LQ. Bei kleiner Fallzahl und kurzem Nachbeobachtungszeitraum kann eine gültige Aussage bezüglich der LQ nach Deszensuschirurgie mit Netzeinlage jedoch noch nicht getroffen werden.
Coulomb explosion of large penetrating molecular clusters
International Nuclear Information System (INIS)
Wegner, H.E.; Thieberger, P.
1981-01-01
The main purpose of these Coulomb explosion measurements is to determine what kind of structure these and other complex molecules may have and also to determine what other special phenomena may come into play as these complex molecules pass through matter. Although the first preliminary measurements involving the Coulomb explosion of these molecules was reported at this workshop last year, the results are briefly summarized before going on to the more recent measurements obtained with a completely new kind of detector system. This new image intensifier detector system, coupled with a microcomputer, has proven to be a valuable tool in the study of the Coulomb explosion of complex molecules that penetrate matter. In the future, with some additional improvements in the system, and much better statistics for most of the molecules studied to date, it is expected that much new information will be gained about the structure of many kinds of complex molecular ions including the special effects that may be encountered when these fast molecular ions penetrate matter
Velocity-induced heavy quarkonium dissociation using the gauge-gravity correspondence
Patra, Binoy Krishna; Khanchandani, Himanshu; Thakur, Lata
2015-10-01
Using the gauge-gravity duality, we have obtained the potential between a heavy quark and an antiquark pair, which is moving perpendicular to the direction of orientation, in a strongly coupled supersymmetric hot plasma. For this purpose we work on a metric in the gravity side, viz. Ouyang-Klebanov-Strassler black hole geometry, of which the dual in the gauge theory side runs with the energy and hence proves to be a better background for thermal QCD. The potential obtained has a confining term both in the vacuum and in a medium, in addition to the Coulomb term alone, usually reported in the literature. As the velocity of the pair is increased, the screening of the potential gets weakened, which may be understood by the decrease of the effective temperature with the increase of the velocity. The crucial observation of our work is that, beyond a critical separation of the heavy quark pair, the potential develops an imaginary part which is nowadays understood to be the main source of dissociation. The imaginary part is found to vanish at small r , thus agreeing with the perturbative result. Finally we have estimated the thermal width for the ground and first excited states and found that nonzero rapidities lead to an increase of thermal width. This implies that the moving quarkonia dissociate more easily than the static ones, which agrees with other calculations. However, the width in our case is larger than other calculations due to the presence of confining terms.
Testing the Predictive Power of Coulomb Stress on Aftershock Sequences
Woessner, J.; Lombardi, A.; Werner, M. J.; Marzocchi, W.
2009-12-01
Empirical and statistical models of clustered seismicity are usually strongly stochastic and perceived to be uninformative in their forecasts, since only marginal distributions are used, such as the Omori-Utsu and Gutenberg-Richter laws. In contrast, so-called physics-based aftershock models, based on seismic rate changes calculated from Coulomb stress changes and rate-and-state friction, make more specific predictions: anisotropic stress shadows and multiplicative rate changes. We test the predictive power of models based on Coulomb stress changes against statistical models, including the popular Short Term Earthquake Probabilities and Epidemic-Type Aftershock Sequences models: We score and compare retrospective forecasts on the aftershock sequences of the 1992 Landers, USA, the 1997 Colfiorito, Italy, and the 2008 Selfoss, Iceland, earthquakes. To quantify predictability, we use likelihood-based metrics that test the consistency of the forecasts with the data, including modified and existing tests used in prospective forecast experiments within the Collaboratory for the Study of Earthquake Predictability (CSEP). Our results indicate that a statistical model performs best. Moreover, two Coulomb model classes seem unable to compete: Models based on deterministic Coulomb stress changes calculated from a given fault-slip model, and those based on fixed receiver faults. One model of Coulomb stress changes does perform well and sometimes outperforms the statistical models, but its predictive information is diluted, because of uncertainties included in the fault-slip model. Our results suggest that models based on Coulomb stress changes need to incorporate stochastic features that represent model and data uncertainty.
Genetische Aspekte der Osteoporose
Directory of Open Access Journals (Sweden)
Obermayer-Pietsch B
1998-01-01
Full Text Available Eine genetische Grundlage der Osteoporose wird neben Umwelteinflüssen seit langem vermutet. Bei Familien- und Zwillingsuntersuchungen wurden erbliche Einflüsse von etwa 46-75 % auf die Knochendichte - abhängig von den Meßorten - festgestellt. Neben einer genetischen Belastung durch eine betroffene Mutter wurde auch ein väterlicher Einfluß auf die Ausprägung der individuellen Knochendichte nachgewiesen. Verschiedenste Kandidatengene wurden bisher untersucht. Bedeutende Beiträge dazu sind in den genetischen Polymorphismen von Östrogen- und anderen Hormonrezeptoren und anderen wichtigen Genorten zu sehen. Eine Durchleuchtung des genetischen Hintergrundes der Osteoporose kann in Zukunft verbesserte Möglichkeiten der Früherkennung und Differenzierung der Diagnostik eröffnen und damit zu neuen Strategien für Prophylaxe und Therapie der Osteoporose führen.
The light-cone gauge in Polyakov's theory of strings and its relation to the conformal gauge
International Nuclear Information System (INIS)
Tzani, R.
1989-01-01
The author studies the string theory as a gauge theory. The analysis includes the formulation of the interacting bosonic string by fixing the Gervais-Sakita light-cone gauge in Polyakov's path-integral formulation of the theory and the study of the problem of changing gauge in string theory in the context of the functional formulation of the theory. The main results are the following: Mandelstam's picture is obtained from the light-cone gauge fixed Polyakov's theory. Due to the off-diagonal nature of the gauge, the calculation of the determinants differs from the usual (conformal gauge) case. The regularization of the functional integrals associated with these determinants is done by using the conformal-invariance principle. He then shows that the conformal anomaly associated with this new gauge fixing is canceled at dimensions of space-time d = 26. Studying the problem of changing gauge in string theory, he shows the equivalence between the light-cone and conformal gauge in the path-integral formulation of the theory. In particular, by performing a proper change of variables in the commuting and ghost fields in the Polyakov path-integral, the string theory in the conformal gauge is obtained from the light-cone gauge fixed expression. Finally, the problem of changing gauge is generalized to the higher genus surfaces. It is shown that the string theory in the conformal gauge is equivalent to the light-cone gauge fixed theory for surface with arbitrary number of handles
Transgenerationale Wertevermittlung in der Familie
DEFF Research Database (Denmark)
Demuth, Carolin
2013-01-01
Der vorliegende Beitrag geht der Frage nach, inwiefern sich in den biografisch-narrativen Konstruktionen junger Erwachsener transgenerationale Aspekte der Identifizierung bzw. Abgrenzung zu den Wertevorstellungen der Ursprungsfamilie finden lassen. Besonderes Augenmerk liegt hierbei auf den Dimen...
Gauge see-saw: A mechanism for a light gauge boson
Energy Technology Data Exchange (ETDEWEB)
Lee, Hye-Sung, E-mail: hlee@ibs.re.kr; Seo, Min-Seok, E-mail: minseokseo@ibs.re.kr
2017-04-10
There has been rapidly growing interest in the past decade in a new gauge boson which is considerably lighter than the standard model Z boson. A well-known example of this kind is the so-called dark photon, and it is actively searched for in various experiments nowadays. It would be puzzling to have a new gauge boson which is neither massless nor electroweak scale, but possesses a rather small yet nonzero mass. We present a mechanism that can provide a light gauge boson as a result of a mass matrix diagonalization.
Yamada, Toshishige; Yamada, Hidenori; Lohn, Andrew J; Kobayashi, Nobuhiko P
2011-02-04
Detailed electron transport analysis is performed for an ensemble of conical indium phosphide nanowires bridging two hydrogenated n(+)-silicon electrodes. The current-voltage (I-V) characteristics exhibit a Coulomb staircase in the dark with a period of ∼ 1 V at room temperature. The staircase is found to disappear under light illumination. This observation can be explained by assuming the presence of a tiny Coulomb island, and its existence is possible due to the large surface depletion region created within contributing nanowires. Electrons tunnel in and out of the Coulomb island, resulting in the Coulomb staircase I-V. Applying light illumination raises the electron quasi-Fermi level and the tunneling barriers are buried, causing the Coulomb staircase to disappear.
Energy Technology Data Exchange (ETDEWEB)
Bettzuege, Marc Oliver [Koeln Univ. (Germany). Energiewirtschaftliches Inst. (ewi)
2018-01-15
In the area of climate and energy policy, exploratory talks over the past few months have shown how important a common target architecture is as a compass for the coming legislative period. Three different levels can be distinguished: Paris (and thus Europe), Germany, sectors in Germany. Finding a balanced climate policy solution requires more exchange of views and less political dirigisme. In a dialogue between state and economy development paths could be spelled out together. [German] Im Bereich der Klima- und Energiepolitik haben die Sondierungsgespraeche in den vergangenen Monaten gezeigt, wie wichtig eine gemeinsame Zielarchitektur als Kompass fuer die kommende Legislaturperiode ist. Drei unterschiedliche Ebenen sind hierbei zu unterscheiden: Paris (und damit Europa), Deutschland, Sektoren in Deutschland. Bei der Suche nach einer ausgewogenen klimapolitischen Loesung sind mehr Meinungsaustausch und weniger politischer Dirigismus gefragt. In einem Dialog zwischen Staat und Wirtschaft koennten Entwicklungspfade gemeinsam ausbuchstabiert werden.
Directory of Open Access Journals (Sweden)
Shusha Niederberger
2014-06-01
Full Text Available Der Begriff der Medienkunst wird mit fortschreitender Medialisierung der Welt immer problematischer. Die Digitalisierung hat alle künstlerischen Medien (ob technische oder nicht als Medien sichtbar gemacht und deren Verhältnis untereinander grundlegend verändert. Rosalind Krauss bezeichnet dieses neue Verhältnis als "post-medium condition" (Krauss 2000. Wenn wir also von der Medienkunst etwas über Medien lernen wollen, was für eine Medienpädagogik nutzbar ist, müssen wir die Entgrenzung des Medialen berücksichtigen. Diese macht die Abgrenzung von Medienkunst von anderen Künsten sehr schwierig, da eine solche künstlerische Praxis weder an formalen, inhaltlichen oder materiellen Eigenschaften festgemacht werden kann. Ich schlage in diesem Text vor, die Medienkunst in ihren methodischen Strategien zu betrachten. Ihre Referenzen in der Kunstgeschichte sind dabei die Konzeptkunst und die Institutionskritik, als kulturgeschichtlichen Hintergrund komme ich auf die Kybernetik zurück. Im vorliegenden Essay möchte ich versuchen, Anschlussmöglichkeiten einer kritischen Medienpädagogik an die aus der Kybernetik entstandene gegenwärtige Netzwerkkultur zu formulieren. Netzwerkkultur bezeichnet dabei nicht die spezifischen Technologien des Internets wie das Social Web, sondern die aus dem Geiste der Kybernetik entstandenen Formen vernetzter Handlungsmöglichkeiten, zu denen unter anderen auch das Social Web gehören.
The singularity structure of scale-invariant rank-2 Coulomb branches
Argyres, Philip C.; Long, Cody; Martone, Mario
2018-05-01
We compute the spectrum of scaling dimensions of Coulomb branch operators in 4d rank-2 N=2 superconformal field theories. Only a finite rational set of scaling dimensions is allowed. It is determined by using information about the global topology of the locus of metric singularities on the Coulomb branch, the special Kähler geometry near those singularities, and electric-magnetic duality monodromies along orbits of the U(1) R symmetry. A set of novel topological and geometric results are developed which promise to be useful for the study and classification of Coulomb branch geometries at all ranks.
Grain dynamics and inter-grain coupling in dusty plasma Coulomb crystals
International Nuclear Information System (INIS)
Rahman, H.U.; Mohideen, U.; Smith, M.A.; Rosenberg, M.; Mendis, D.A.
2001-01-01
We review our results on the lattice structure and the lattice dynamics of dusty plasma Coulomb crystals formed in rectangular conductive grooves. The basic structure appears to be made of mutually repulsive columns of grains confined by the walls of the groove. The columns are oriented along the direction of the electrode sheath electric field. Inter-grain coupling as a function of plasma temperature and density were investigated by measurement of these parameters. A simple phenomenological model wherein the inter-grain spacing along the column results from an attractive electric field induced dipole-dipole force balanced by a repulsive monopole Coulomb force is consistent with observed features of the Coulomb crystal. In addition, here we present some preliminary measurements of the vibration and rotation dynamics of the individual grains in the Coulomb crystal. The thermal energy of the dust grain thus calculated is much less than the inter-grain Coulomb potential energy as required for the formation of stable structures. Also the observed rotational frequency is consistent with the assumption of thermal equilibrium between the dust grains and the neutral gas. (orig.)
Jackson, M I; Hiley, M J; Yeadon, M R
2011-10-13
In the table contact phase of gymnastics vaulting both dynamic and static friction act. The purpose of this study was to develop a method of simulating Coulomb friction that incorporated both dynamic and static phases and to compare the results with those obtained using a pseudo-Coulomb implementation of friction when applied to the table contact phase of gymnastics vaulting. Kinematic data were obtained from an elite level gymnast performing handspring straight somersault vaults using a Vicon optoelectronic motion capture system. An angle-driven computer model of vaulting that simulated the interaction between a seven segment gymnast and a single segment vaulting table during the table contact phase of the vault was developed. Both dynamic and static friction were incorporated within the model by switching between two implementations of the tangential frictional force. Two vaulting trials were used to determine the model parameters using a genetic algorithm to match simulations to recorded performances. A third independent trial was used to evaluate the model and close agreement was found between the simulation and the recorded performance with an overall difference of 13.5%. The two-state simulation model was found to be capable of replicating performance at take-off and also of replicating key contact phase features such as the normal and tangential motion of the hands. The results of the two-state model were compared to those using a pseudo-Coulomb friction implementation within the simulation model. The two-state model achieved similar overall results to those of the pseudo-Coulomb model but obtained solutions more rapidly. Copyright © 2011 Elsevier Ltd. All rights reserved.
Dynamical supersymmetry breaking and gauge anomalies
International Nuclear Information System (INIS)
Zhang, H.
1991-01-01
Some aspects of supersymmetric gauge theories are discussed. It is shown that dynamical supersymmetry breaking does not occur in supersymmetric QED in higher dimensions. The cancellation of both local (perturbative) and global (non-perturbative) gauge anomalies are also discussed in supersymmetric gauge theories. We argue that there is no dynamical supersymmetry breaking in higher dimensions in any supersymmetric gauge theories free of gauge anomalies. It is also shown that for supersymmetric gauge theories in higher dimensions with a compact connected simple gauge group, when the local anomaly-free condition is satisfied, there can be at most a possible Z 2 global gauge anomaly in extended supersymmetric SO(10) (or spin (10)) gauge theories in D=10 dimensions containing additional Weyl fermions in a spinor representation of SO(10) (or spin (10)). In four dimensions with local anomaly-free condition satisfied, the only possible global gauge anomalies in supersymmetric gauge theories are Z 2 global gauge anomalies for extended supersymmetric SP(2N) (N=rank) gauge theories containing additional Weyl fermions in a representation of SP(2N) with an odd 2nd-order Dynkin index. (orig.)
Coulomb Sturmians as a basis for molecular calculations
DEFF Research Database (Denmark)
Avery, John Scales; Avery, James Emil
2012-01-01
mathematical difficulty of evaluating interelectron repulsion integrals when exponential-type orbitals (ETOs) are used. In this paper we show that when many-centre Coulomb Sturmian ETOs are used as a basis, the most important integrals can be evaluated rapidly and accurately by means of the theory...... of hyperspherical harmonics. For the remaining many-centre integrals, Coulomb Sturmians are shown to have advantages over other ETOs. Pilot calculations are performed on N-electron molecules using the Generalized Sturmian Method....
Regularized friction and continuation: Comparison with Coulomb's law
Vigué, Pierre; Vergez, Christophe; Karkar, Sami; Cochelin, Bruno
2016-01-01
International audience; Periodic solutions of systems with friction are difficult to investigate because of the irregular nature of friction laws. This paper examines periodic solutions and most notably stick-slip, on a simple one-degre-of-freedom system (mass, spring, damper, belt), with Coulomb's friction law, and with a regularized friction law (i.e. the friction coefficient becomes a function of relative speed, with a stiffness parameter). With Coulomb's law, the stick-slip solution is co...
Unstable system with Coulomb interaction distorted near the origin
International Nuclear Information System (INIS)
Kerbikov, B.O.
1981-01-01
An unstable system with Coulomb interaction distorted at small distances is considered. The results are applicable to hadronic atoms analysis. A detailed investigation of the model which can be solved exactly is presented. This model contains the separable short-range potential with the Yamaguchi form factor. Closed expressions for the modified effective range function and the Coulomb-modified scattering length ase obtained [ru
Coulomb interference and bending slope in hadron-hadron scattering
International Nuclear Information System (INIS)
Pereira, Flavio I.; Ferreira, Erasmo
1994-01-01
With the purpose of testing the results of QCD calculations on the structure of the forward elastic scattering cross-section, we analyse the coulombic-nuclear interference occurring at small values of the momentum transfer. We emphasize the influence of the hadronic structures on the determination of the Coulomb phase and consequently on the t-dependence of the strong interaction slope parameter. (author)
Frictional Magneto-Coulomb Drag in Graphene Double-Layer Heterostructures.
Liu, Xiaomeng; Wang, Lei; Fong, Kin Chung; Gao, Yuanda; Maher, Patrick; Watanabe, Kenji; Taniguchi, Takashi; Hone, James; Dean, Cory; Kim, Philip
2017-08-04
Coulomb interaction between two closely spaced parallel layers of conductors can generate the frictional drag effect by interlayer Coulomb scattering. Employing graphene double layers separated by few-layer hexagonal boron nitride, we investigate density tunable magneto- and Hall drag under strong magnetic fields. The observed large magnetodrag and Hall-drag signals can be related with Laudau level filling status of the drive and drag layers. We find that the sign and magnitude of the drag resistivity tensor can be quantitatively correlated to the variation of magnetoresistivity tensors in the drive and drag layers, confirming a theoretical formula for magnetodrag in the quantum Hall regime. The observed weak temperature dependence and ∼B^{2} dependence of the magnetodrag are qualitatively explained by Coulomb scattering phase-space argument.
Gauge-invariant variational methods for Hamiltonian lattice gauge theories
International Nuclear Information System (INIS)
Horn, D.; Weinstein, M.
1982-01-01
This paper develops variational methods for calculating the ground-state and excited-state spectrum of Hamiltonian lattice gauge theories defined in the A 0 = 0 gauge. The scheme introduced in this paper has the advantage of allowing one to convert more familiar tools such as mean-field, Hartree-Fock, and real-space renormalization-group approximation, which are by their very nature gauge-noninvariant methods, into fully gauge-invariant techniques. We show that these methods apply in the same way to both Abelian and non-Abelian theories, and that they are at least powerful enough to describe correctly the physics of periodic quantum electrodynamics (PQED) in (2+1) and (3+1) space-time dimensions. This paper formulates the problem for both Abelian and non-Abelian theories and shows how to reduce the Rayleigh-Ritz problem to that of computing the partition function of a classical spin system. We discuss the evaluation of the effective spin problem which one derives the PQED and then discuss ways of carrying out the evaluation of the partition function for the system equivalent to a non-Abelian theory. The explicit form of the effective partition function for the non-Abelian theory is derived, but because the evaluation of this function is considerably more complicated than the one derived in the Abelian theory no explicit evaluation of this function is presented. However, by comparing the gauge-projected Hartree-Fock wave function for PQED with that of the pure SU(2) gauge theory, we are able to show that extremely interesting differences emerge between these theories even at this simple level. We close with a discussion of fermions and a discussion of how one can extend these ideas to allow the computation of the glueball and hadron spectrum
Coulombic Fluids Bulk and Interfaces
Freyland, Werner
2011-01-01
Ionic liquids have attracted considerable interest in recent years. In this book the bulk and interfacial physico-chemical characteristics of various fluid systems dominated by Coulomb interactions are treated which includes molten salts, ionic liquids as well as metal-molten salt mixtures and expanded fluid metals. Of particular interest is the comparison of the different systems. Topics in the bulk phase concern the microscopic structure, the phase behaviour and critical phenomena, and the metal-nonmetal transition. Interfacial phenomena include wetting transitions, electrowetting, surface freezing, and the electrified ionic liquid/ electrode interface. With regard to the latter 2D and 3D electrochemical phase formation of metals and semi-conductors on the nanometer scale is described for a number of selected examples. The basic concepts and various experimental methods are introduced making the book suitable for both graduate students and researchers interested in Coulombic fluids.
Theoretische Konzepte der Physik
Longair, Malcolm S.; Simon, B.; Simon, H.
"Dies ist kein Lehrbuch der theoretischen Physik, auch kein Kompendium der Physikgeschichte ... , vielmehr eine recht anspruchsvolle Sammlung historischer Miniaturen zur Vergangenheit der theoretischen Physik - ihrer "Sternstunden", wenn man so will. Frei vom Zwang, etwas Erschöpfendes vorlegen zu müssen, gelingt dem Autor etwas Seltenes: einen "lebendigen" Zugang zum Ideengebäude der modernen Physik freizulegen, ... zu zeigen, wie Physik in praxi entsteht... Als Vehikel seiner Absichten dienen dem Autor geschichtliche Fallstudien, insgesamt sieben an der Zahl. Aus ihnen extrahiert er das seiner Meinung nach Lehrhafte, dabei bestrebt, mathematische Anachronismen womöglich zu vermeiden... Als Student hätte ich mir diese gescheiten Essays zum Werden unserer heutigen physikalischen Weltsicht gewünscht. Sie sind originell, didaktisch klug und genieren sich auch nicht, von der Faszination zu sprechen, die ... von der Physik ausgeht. Unnötig darauf hinzuweisen, das sie ein gründliches "konventionelles" Studium weder ersetzen wollen noch können, sie vermögen aber, dazu zu ermuntern." #Astronomische Nachrichten (zur englischen Ausgabe)#1
A set-valued force law for spatial Coulomb-Contensou friction
Leine, R.I.; Glocker, C.
2003-01-01
The aim of this paper is to develop a set-valued contact law for combined spatial Coulomb-Contensou friction, taking into account a normal friction torque (drilling friction) and spin. The set-valued Coulomb-Contensou friction law is derived from a non-smooth velocity pseudo potential. A
Strahlungsfeldbedingungen bei der Ionisationsdosimetrie
Krieger, Hanno
Bei der Dosimetrie von Photonenstrahlungen mit luftgefüllten Ionisationskammern werden in diesem Kapitel zwei Grenzfälle unterschieden. Der eine Fall ist die Bedingung des so genannten Sekundärelektronengleichwichts im Kammervolumen. In diesem Fall bestimmen ausschließlich die Photonen im Messvolumen die dosimetrische Anzeige. Der zweite Grenzfall ist gegeben, wenn das Luftvolumen und die Kammer das Strahlungsfeld im Phantom so wenig stören, dass der Sekundärelektronenfluss unverändert bleibt. Diese Bedingungen nennt man BRAGG-GRAY-Bedingungen. Beide Grenzfälle sind in der Praxis nur näherungsweise zu verwirklichen. Abweichungen müssen durch entsprechende Korrekturen oder Kalibrierungen berücksichtigt werden.
Organisationsaspekte in der Umsetzung
Balck, Henning; Bungard, Walter; Hofmann, Karsten; Ganz, Walter; Schwenker, Burkhard; Hanßen, Dirk; Meindl, Rudolf; Schloske, Alexander; Thieme, Paul; Teufel, Peter
Strukturbrüche sind eine der Hauptursachen für die Schwierigkeiten vieler Unternehmen, ihre Organisationsform zu modernisieren und vor allem turbulenten Marktbedingungen anzupassen. Klassische Beispiele für Strukturbrüche finden sich in der Spaltung von Aufbau- und Ablauforganisation, der Spaltung von Produktion und Dienstleistung oder der Spaltung von Planung und Ausführung. Ein wirkungsvoller Ansatz zur Überwindung solcher Spaltungen ist eine Art Versöhnungsmuster: die Polare Organisation. Wesentliche Elemente dieser Organisationsform sind ihr Netzwerkcharakter, kooperatives Zusammenwirken, eine hohe Kommunikationsintensität und eine polare Koppelung der kommunizierenden Partner oder - in abstrahierter Form - die organisierte Balance erfolgskritischer Gegensätze, wie Kosten und Qualität.
Restoration of the local gauge symmetry and color confinement in non-Abelian gauge theories
International Nuclear Information System (INIS)
Hata, Hiroyuki
1982-01-01
Restoration of the local gauge symmetry and its connection to color confinement is investigated in non-Abelian gauge theories with covariant gauge fixing. We consider the Noether current J sub(μ,#betta#)sup(a) of the local gauge transformation with transformation functions #betta#sup(b)(x) linear in x sub(μ); #betta#sup(b)(x) = delta sup(ab)x sub(#betta#). This current is conserved only in the physical subspace of the state vector space and in perturbation theory contains a massless pole communicating to the gauge field. We define the local gauge symmetry restoration as the disappearance of this massless ''Goldstone'' pole from J sub(μ,#betta#)sup(a). The restoration condition is obtained and it coincides exactly with the color confinement criterion proposed earlier by Kugo and Ojima. Quarks and other colored particles are shown to be confined in the local gauge symmetry restored phase by using the Ward identities of J sub(μ,#betta#)sup(a). (author)
Extended gauge sectors at future colliders: Report of the New Gauge Boson Subgroup
International Nuclear Information System (INIS)
Rizzo, T.G.
1996-12-01
The author summarizes the results of the New Gauge Boson Subgroup on the physics of extended gauge sectors at future colliders as presented at the 1996 Snowmass workshop. He discusses the direct and indirect search reaches for new gauge bosons at both hadron and lepton colliders as well as the ability of such machines to extract detailed information on the couplings of these particles to the fermions and gauge bosons of the Standard Model. 41 refs., 18 figs., 5 tabs
Die Mythen von der Globalisierung
DEFF Research Database (Denmark)
Nell, Phillip; Schmitt, Jan; Decreton, Benoit
2017-01-01
Der Wissensstand über den Grad und die Art der Globalisierung ist viel niedriger als angenommen. Daraus entstehen Fehleinschätzungen.......Der Wissensstand über den Grad und die Art der Globalisierung ist viel niedriger als angenommen. Daraus entstehen Fehleinschätzungen....
Core polarization and Coulomb displacement energies
International Nuclear Information System (INIS)
Shlomo, S.; Love, W.G.
1982-01-01
The contributions of core polarization terms (other than the Auerbach-Kahana-Weneser (AKW) effect) to Coulomb displacement energies of mirror nuclei near A = 16 and A = 40 are examined within the particle-vibration coupling model. The parameters of the model are determined using updated data on the locations and strengths of multipole core excitations. In the absence of relevant data an energy-weighted sum rule (EWSR) is exploited. Taking into account multipole excitations up to L = 5 and subtracting the contributions which are due to short-range correlations, significant contributions (1-3%) to ΔEsub(c) are found. These corrections arise from particle coupling to low-lying collective states (long-range correlations). The implications of these results on the Coulomb energy problem are discussed. (Auth.)
Part-turn gearboxes for electric actuators; Schwenkgetriebe fuer elektrische Stellantriebe
Energy Technology Data Exchange (ETDEWEB)
Herbstritt, M. [Riester (W.) GmbH und Co. KG, Muellheim (Germany)
2002-09-01
Different types of gearboxes provide a useful complement to the electric actuator type ranges. The gearboxes can be combined with the actuators in many ways. Multi-turn actuators, for example, can be turned into part-turn actuators. When using a modular system, a suitable solution for almost any automation task in the field of industrial valves can be found. (orig.) [German] Sinnvoll ergaenzt werden elektrische Stellantriebe fuer Armaturen durch verschiedene Arten von Getrieben. Die Getriebe sind in vielfaeltiger Weise mit den Stellantrieben kombinierbar. So werden beispielsweise aus Drehantrieben Schwenkantriebe. Mit einem Baukasten-System laesst sich so fuer nahezu jede Automatisierungsaufgabe im Bereich der Industriearmaturen eine passende Loesung finden. (orig.)
Energy Technology Data Exchange (ETDEWEB)
Battenberg, S.; Naeveke, R. [Gesellschaft fuer Biotechnologische Forschung mbH, Braunschweig (Germany). Bereich Mikrobiologie
1999-07-01
Mechanical disintegration breaks up the flake structure of excess sludge and solubilizes organic constituents. Bacterial cells are rendered soluble. Thermal conditioning of excess sludge, too, can release sludge constituents. This makes for enhanced and accelerated hydrolysis of polymeric sludge constituents in subsequent anaerobic processing. The yield of useful biogas is increased. (orig.) [German] Durch die mechanische Desintegration von Ueberschussschlamm wird die Flockenstruktur zerschlagen und organische Inhaltsstoffe werden in Loesung gebracht. Bakterienzellen werden aufgeschlossen. Auch durch eine thermische Behandlung von Ueberschussschlamm koennen Schlamminhaltsstoffe freigesetzt werden. Dadurch wird bei einer anschliessenden anaeroben Behandlung die Hydrolyse der polymeren Schlamminhaltsstoffe gefoerdert und beschleunigt. Die Ausbeute an verwertbarem Biogas wird gesteigert. (orig.)
Sub-Coulomb heavy ion neutron transfer reactions and neutron orbit sizes
International Nuclear Information System (INIS)
Phillips, W.R.
1976-01-01
Direct transfer reactions below the Coulomb barrier offer the best means of determining neutron densities near the nuclear surface. This paper describes how heavy ion sub-Coulomb transfer can be used to determine the rms radii of neutron orbits in certain nuclei. The theoretical background is outlined and problems associated with the comparison of experiment and theory are discussed. Experiments performed to calibrate sub-Coulomb heavy ion transfer reactions are presented, and some comments are made on the relative roles of light and heavy ion reactions. Preliminary values for the rms radii of neutron orbits and neutron excesses extracted from recent experiments are given, and some remarks are made concerning the implications of these results for the triton wave function and for the Coulomb energy difference anomaly. (author)
11Li Breakup on 208 at energies around the Coulomb barrier.
Fernández-García, J P; Cubero, M; Rodríguez-Gallardo, M; Acosta, L; Alcorta, M; Alvarez, M A G; Borge, M J G; Buchmann, L; Diget, C A; Falou, H A; Fulton, B R; Fynbo, H O U; Galaviz, D; Gómez-Camacho, J; Kanungo, R; Lay, J A; Madurga, M; Martel, I; Moro, A M; Mukha, I; Nilsson, T; Sánchez-Benítez, A M; Shotter, A; Tengblad, O; Walden, P
2013-04-05
The inclusive breakup for the (11)Li + (208)Pb reaction at energies around the Coulomb barrier has been measured for the first time. A sizable yield of (9)Li following the (11)Li dissociation has been observed, even at energies well below the Coulomb barrier. Using the first-order semiclassical perturbation theory of Coulomb excitation it is shown that the breakup probability data measured at small angles can be used to extract effective breakup energy as well as the slope of B(E1) distribution close to the threshold. Four-body continuum-discretized coupled-channels calculations, including both nuclear and Coulomb couplings between the target and projectile to all orders, reproduce the measured inclusive breakup cross sections and support the presence of a dipole resonance in the (11)Li continuum at low excitation energy.
Mirror symmetry and Coulomb effects in light N ≅ Z nuclei
International Nuclear Information System (INIS)
Bentley, M.A.; Williams, S.J.; Joss, D.T.
2002-01-01
Some latest results from gamma-ray spectroscopic studies of high spin states of isobaric multiplets are presented. An experimental programme is underway to examine exited states of isobaric multiplets of total isospin T 1/2 and T = 1 and the comparison of energies of excited states can be interpreted in terms of Coulomb effects. Through a systematic study of these Coulomb effects, and through examination of the calculated Coulomb energies from full pf-shell model calculations, it is now becoming clear that measurement of Coulomb energies can yield very detailed information on the evolution of nuclear structure phenomena as a function of energy and angular momentum. In this contribution, latest results of studies of isobaric analogue states at high spin in the A = 50, 51 and 53 systems are presented. (author)
Der Wandel in der Benutzung des World Wide Webs
Weinreich, H.; Heinecke, A.; Obendorf, H.; Paul, H.; Mayer, M.; Herder, E.
2006-01-01
Dieser Beitrag präsentiert ausgewählte Ergebnisse einer Langzeitstudie mit 25 Teilnehmern zur Benutzung des Webs. Eine Gegenüberstellung mit den Ergebnissen der letzten vergleichbaren Studien offenbart eine deutliche Veränderung im Navigationsverhalten der Nutzer. Neue Angebote und Dienste des Webs
Parastatistics and gauge symmetries
International Nuclear Information System (INIS)
Govorkov, A.B.
1982-01-01
A possible formulation of gauge symmetries in the Green parafield theory is analysed and the SO(3) gauge symmetry is shown to be on a distinct status. The Greenberg paraquark hypothesis turns out to be not equivalent to the hypothesis of quark colour SU(3)sub(c) symmetry. Specific features of the gauge SO(3) symmetry are discussed, and a possible scheme where it is an exact subgroup of the broken SU(3)sub(c) symmetry is proposed. The direct formulation of the gauge principle for the parafield represented by quaternions is also discussed
Implementing general gauge mediation
International Nuclear Information System (INIS)
Carpenter, Linda M.; Dine, Michael; Festuccia, Guido; Mason, John D.
2009-01-01
Recently there has been much progress in building models of gauge mediation, often with predictions different than those of minimal gauge mediation. Meade, Seiberg, and Shih have characterized the most general spectrum which can arise in gauge-mediated models. We discuss some of the challenges of building models of general gauge mediation, especially the problem of messenger parity and issues connected with R symmetry breaking and CP violation. We build a variety of viable, weakly coupled models which exhibit some or all of the possible low energy parameters.
Pädagogik der sexuellen Differenz
Directory of Open Access Journals (Sweden)
Heike Kahlert
2007-07-01
Full Text Available Der von der Freiburger Philosophin und Theologin Andrea Günter herausgegebene Sammelband ist aus einer deutsch-italienischen Tagung zu Kernfragen der Pädagogik hervorgegangen, die im Sommer 2003 an der Evangelischen Akademie Arnoldshain durchgeführt wurde und deren gemeinsames Orientierungsfeld die Einflüsse der politischen Bildungsarbeit der Veroneser Philosophinnengemeinschaft Diotima bilden. Die insgesamt elf Aufsätze von Pädagoginnen, Theologinnen und Politikwissenschaftlerinnen, darunter ein aus dem Italienischen übersetzter Grundlagentext von Anna Maria Piussi, leisten einen wichtigen Beitrag zur „kulturellen Übersetzung“ des italienischen Differenzansatzes in die deutschsprachige politische und vor allem pädagogische Praxis.
Anyonic states in Chern-Simons theory
International Nuclear Information System (INIS)
Haller, K.; Lim-Lombridas, E.
1994-01-01
We discuss the canonical quantization of Chern-Simons theory in 2+1 dimensions, minimally coupled to a Dirac spinor field, first in the temporal gauge and then in the Coulomb gauge. In our temporal gauge formulation, Gauss's law and the gauge condition A 0 =0 are implemented by embedding the formulation in an appropriate physical subspace. We construct a Fock space of charged particle states that satisfy Gauss's law, and show that they obey fermion, not fractional statistics. The gauge-invariant spinor field that creates these charged states from the vacuum obeys the anticommutation rules that generally apply to spinor fields. The Hamiltonian, when described in the representation in which the charged fermions are the propagating particle excitations that obey Gauss's law, contains an interaction between charge and transverse current densities. We observe that the implementation of Gauss's law and the gauge condition does not require us to use fields with graded commutator algebras or particle excitations with fractional statistics. In our Coulomb gauge formulation, we implement Gauss's law and the gauge condition ∂ l A l =0 by the Dirac-Bergmann procedure. In this formulation, the constrained gauge fields become functionals of the spinor fields, and are not independent degrees of freedom. The formulation in the Coulomb gauge confirms the results we obtained in the temporal gauge: The ''Dirac-Bergmann'' anticommutation rule for the charged spinor fiels ψ and ψ degree that have both been constrained to obey Gauss's law is precisely identical to the canonical spinor anticommutation rule that generates standard fermion statistics. And we also show that the Hamiltonians for charged particle states in our temporal and Coulomb gauge formulations are identical, once Gauss's law has been implemented in both cases
Altun, Ufuk
2005-01-01
Arbeitszeitpolitik und Arbeitszeitgestaltung haben seit dem Tarifkompromiss im Jahre 1984 in der Metall-, und Elektroindustrie in der politischen und wissenschaftlichen Diskussion einen immensen Bedeutungszuwachs erfahren. Die Forderungen nach einer flexibleren Arbeitszeitgestaltung haben zeitgleich sowohl aus der Globalisierungsdiskussion und der Debatte um die Wettbewerbsfähigkeit des "Wirtschaftsstandorts Deutschland" heraus wie auch aus beschäftigungspolitischen Gründen neuen Auftrieb bek...
Typologische Aufgaben der historischen Textlinguistik
Directory of Open Access Journals (Sweden)
Ingo Warnke
1995-12-01
Full Text Available Die gegenwärtige germanistische Historiolinguistik ist geprägt durch eine pragmatische Ausweitung ihres traditionell sprachstrukturellen Erkenntnisinteresses. Ausdruck dieser Entwicklung ist z.B. die gänzliche Neubearbeitung der Sprachgeschichte von P. von Polenz (1991 und 1994, die an Stelle der wiederholt neu aufgelegten und auf H. Sperber (1926 gründenden Geschichte der deutschen Sprache (von Polenz 1978 erschienen ist und insbesondere eine "sozial- und mediengeschichtliche Fundierung" (ebd., 3 anstrebt, wobei neben anderen Aspekten als Schwerpunkt der Darstellung explizi1t die Sprachpragmatik genannt wird (ebd.. Sind die konzeptionellen Ecksteine einer solchen pragmatischen Sprachgeschichtsschreibung auch schon Anfang der 1980er Jahre insbesondere mit H. Sitta (1980 und D. Cherubim (1984 gesetzt, so verstärkt sich das sprachhandlungsbezogene Interesse an der Geschichte des Deutschen erst in jüngster Zeit. Die Entwicklung läuft dabei parallel zur Konstituierung eines pragmatischen Paradigmas, das als Gemeinschaftswerk geisteswissenschaftlicher Forschung ebenfalls in den 1980er Jahren an Bedeutung gewann und als dessen notwendige Folge H. Stachowiak ([Hg.] 1986, XVII einen '"Paradigmawechsel' großen Stils" prophezeit hat.1 Bei den Pragmatisierungstendenzen sprachgeschichtlicher Fragestellungen kommt der historischen Dimensionierung textlinguistischer Erkenntnisfelder besondere Bedeutung zu. Es ist bekannt, daß die in den späten 1960er und 70er Jahren begründete Textlinguistik zunächst ebenso ahistorisch gewesen ist, wie die Historiolinguistik apragmatisch. Doch mit der fortschreitenden Rezeption sprachhandlungsorientierter Ansätze in der Sprachgeschichte gewann der Text i.S. einer komplexen sprachlichen Handlung (vgl. u.a. Sandig 1978, 69f., 99ff., 157f. als Analyseobjekt für die pragmatische Orientierung der Sprachgeschichte zunehmend an Bedeutung. In diesem Zusammenhang ist die Forderung nach textlinguistischer bzw
International Nuclear Information System (INIS)
Meade, Patrick; Seiberg, Nathan; Shih, David
2009-01-01
We give a general definition of gauge mediated supersymmetry breaking which encompasses all the known gauge mediation models. In particular, it includes both models with messengers as well as direct mediation models. A formalism for computing the soft terms in the generic model is presented. Such a formalism is necessary in strongly-coupled direct mediation models where perturbation theory cannot be used. It allows us to identify features of the entire class of gauge mediation models and to distinguish them from specific signatures of various subclasses. (author)
Absence of Debye screening in the quantum Coulomb system
International Nuclear Information System (INIS)
Brydges, D.C.; Keller, G.
1994-01-01
We present an approximation to the quantum Coulomb plasma at equilibrium which captures the power-law violations of Debye screening which have been reported in recent papers. The objectives are (1) to produce a simpler model which we will study in forthcoming papers, and (2) to develop a strategy by which the absence of screening can be proven for the low-density quantum Coulomb plasma itself
Kusnezow, Wlad
2007-01-01
Obwohl Protein-Mikroarrays ursprünglich aus dem gut entwickelten und fest etablierten DNA-Pendant entstanden sind, repräsentierte jedoch die Umstellung der Mikroarray-Technik von der DNA- auf die Proteinanalyse aufgrund der enormen physikalisch-chemischen Variabilität der Proteine, deren relativ niedrigen Stabilität und der komplexen Mikrospot-Kinetik eine große technologische Herausforderung. Deshalb setzt das Vorhaben, die Technik der Antikörper–Mikroarrays von ihrem konzeptuellen Zustand a...
The holomorphicity of the gauge coupling constant in supersymmetric gauge theories
International Nuclear Information System (INIS)
Li, H.
1993-01-01
Holomorphicity is the analytical dependence of the gauge coupling function, f = 1/g 2 + Θ/8π 2 , on the chiral fields in supergravity and supersymmetric gauge theories. The holomorphic property of 1/g 2 in supersymmetric gauge theories is studied by calculating its dependence on the mass matrix. The general representations of the mass matrix allowed by the constraints of gauge invariance is considered, and calculate the one- and two-loop corrections to 1/g 2 for both super QED and super Yang-Mills theories. For the massive mass matrix it is shown that one- and two-loop corrections to the gauge coupling constant are holomorphic. The reason for two-loop holomorphicity is that the second order logarithmic terms cancel out. For the mass matrix with at least one zero mode, it is recognized that there are two distinct cases which we call pseudo massive and intrinsically massless. For the case of pseudo mass matrix, the reducible representation of the gauge group is (i) complex with equal numbers of irreducible representations and their conjugates, (ii) real, or (iii) pseudo-real. Even though there are massless modes, it is found that the dependence of the gauge coupling constant on the mass matrix is holomorphic. This holomorphicity follows because the mass matrix can be perturbed to regularize the infrared divergence. For the case of intrinsically massless mass matrix, a reducible complex representation with unequal numbers of irreducible representations and their conjugates. The author shows that loop corrections to the gauge coupling constant are non-holomorphic. The reason is an infrared momentum cutoff is used which spins holomorphicity. The results show that, for the pseudo massive case, even though there is an infrared divergence, the one- and two-loop corrections are still holomorphic. Hence, it is concluded that non-holomorphicity is caused by the unbalanced numbers of families and antifamilies in the complex representation
Three-dimensional oscillator and Coulomb systems reduced from Kaehler spaces
International Nuclear Information System (INIS)
Nersessian, Armen; Yeranyan, Armen
2004-01-01
We define the oscillator and Coulomb systems on four-dimensional spaces with U(2)-invariant Kaehler metric and perform their Hamiltonian reduction to the three-dimensional oscillator and Coulomb systems specified by the presence of Dirac monopoles. We find the Kaehler spaces with conic singularity, where the oscillator and Coulomb systems on three-dimensional sphere and two-sheet hyperboloid originate. Then we construct the superintegrable oscillator system on three-dimensional sphere and hyperboloid, coupled to a monopole, and find their four-dimensional origins. In the latter case the metric of configuration space is a non-Kaehler one. Finally, we extend these results to the family of Kaehler spaces with conic singularities
Enhanced Bulk-Edge Coulomb Coupling in Fractional Fabry-Perot Interferometers.
von Keyserlingk, C W; Simon, S H; Rosenow, Bernd
2015-09-18
Recent experiments use Fabry-Perot (FP) interferometry to claim that the ν=5/2 quantum Hall state exhibits non-Abelian topological order. We note that the experiments appear inconsistent with a model neglecting bulk-edge Coulomb coupling and Majorana tunneling, so we reexamine the theory of FP devices. Even a moderate Coulomb coupling may strongly affect some fractional plateaus, but very weakly affect others, allowing us to model the data over a wide range of plateaus. While experiments are consistent with the ν=5/2 state harboring Moore-Read topological order, they may have measured Coulomb effects rather than an "even-odd effect" due to non-Abelian braiding.
Engineering drag currents in Coulomb coupled quantum dots
Lim, Jong Soo; Sánchez, David; López, Rosa
2018-02-01
The Coulomb drag phenomenon in a Coulomb-coupled double quantum dot system is revisited with a simple model that highlights the importance of simultaneous tunneling of electrons. Previously, cotunneling effects on the drag current in mesoscopic setups have been reported both theoretically and experimentally. However, in both cases the sequential tunneling contribution to the drag current was always present unless the drag level position were too far away from resonance. Here, we consider the case of very large Coulomb interaction between the dots, whereby the drag current needs to be assisted by cotunneling events. As a consequence, a quantum coherent drag effect takes place. Further, we demonstrate that by properly engineering the tunneling probabilities using band tailoring it is possible to control the sign of the drag and drive currents, allowing them to flow in parallel or antiparallel directions. We also show that the drag current can be manipulated by varying the drag gate potential and is thus governed by electron- or hole-like transport.
Sensitivity of electrospray molecular dynamics simulations to long-range Coulomb interaction models.
Mehta, Neil A; Levin, Deborah A
2018-03-01
Molecular dynamics (MD) electrospray simulations of 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIM-BF_{4}) ion liquid were performed with the goal of evaluating the influence of long-range Coulomb models on ion emission characteristics. The direct Coulomb (DC), shifted force Coulomb sum (SFCS), and particle-particle particle-mesh (PPPM) long-range Coulomb models were considered in this work. The DC method with a sufficiently large cutoff radius was found to be the most accurate approach for modeling electrosprays, but, it is computationally expensive. The Coulomb potential energy modeled by the DC method in combination with the radial electric fields were found to be necessary to generate the Taylor cone. The differences observed between the SFCS and the DC in terms of predicting the total ion emission suggest that the former should not be used in MD electrospray simulations. Furthermore, the common assumption of domain periodicity was observed to be detrimental to the accuracy of the capillary-based electrospray simulations.
Room temperature Coulomb blockade mediated field emission via self-assembled gold nanoparticles
Energy Technology Data Exchange (ETDEWEB)
Wang, Fei [College of Physics and Electronics, Central South University, Changsha, Hunan 410073 (China); College of Science, National University of Defense Technology, Changsha, Hunan 410073 (China); Fang, Jingyue, E-mail: fjynudt@aliyun.com [College of Science, National University of Defense Technology, Changsha, Hunan 410073 (China); Chang, Shengli; Qin, Shiqiao; Zhang, Xueao [College of Science, National University of Defense Technology, Changsha, Hunan 410073 (China); Xu, Hui, E-mail: cmpxhg@csu.edu.cn [College of Physics and Electronics, Central South University, Changsha, Hunan 410073 (China)
2017-02-05
Coulomb blockade mediated field-emission current was observed in single-electron tunneling devices based on self-assembled gold nanoparticles at 300 K. According to Raichev's theoretical model, by fixing a proper geometric distribution of source, island and drain, the transfer characteristics can be well explained through a combination of Coulomb blockade and field emission. Coulomb blockade and field emission alternately happen in our self-assembled devices. The Coulomb island size derived from the experimental data is in good agreement with the average size of the gold nanoparticles used in the device. The integrated tunneling can be adjusted via a gate electrode. - Highlights: • The phenomenon of single-electron field emission in a transistor setting using self-assembled gold nanoparticles was investigated. • The transfer characteristics can be well explained by the model that is a combination of Coulomb blockage and field emission. • This transport mechanism is novel and may be used in many applications in field emission devices.
Die Grundlagen der Arithmetik. Eine logisch mathematische Untersuchung über den Begriff der Zahl
Frege, Gottlob
1996-01-01
Auf die Frage, was die Zahl Eins sei, oder was das Zeichen 1 bedeute, wird man meistens die Antwort erhalten: nun, ein Ding. Und wenn man dann darauf aufmerksam macht, dass der Satz "die Zahl Eins ist ein Ding" keine Definition ist, weil auf der einen Seite der bestimmte Artikel, auf der andern der unbestimmte steht, dass er nur besagt, die Zahl Eins gehöre zu den Dingen, aber nicht, welches Ding sie sei, so wird man vielleicht aufgefordert, sich irgendein Ding zu wählen, das man Eins nenn...
Schnabl, Alexander; Dippenaar, Sarah; Müllbacher, Sandra; Skrivanek, Isabella; Weberberger, Irene
2011-01-01
aus dem Inhaltsverzeichnis: Einleitung; Kultur und Tourismus - ökonomische Aspekte; Untersuchungsmethode; Ökonomische Effekte der Ausgaben der Vereinigten Bühnen Wien; Ökonomische Effekte der Ausgaben der BesucherInnen der Vereinigten Bühnen Wien; Executive Summary; Literaturverzeichnis;
Muslim, Zahim Mohammed
2010-01-01
„Lessing und der Islam“ beschäftigt sich unparteiisch mit Lessings Auseinandersetzung mit dem Islam. Die Arbeit setzt sich das Ziel, den Leser und den Literaturkennern sowie der deutschen Bibliothek der Germanistik etwas von Lessings Auseinandersetzung mit dem Islam in die Hand zu geben, die bis heute als großes Modell für die interkulturelle und interreligiöse Menschheitstoleranzdebatte im Gedächtnis der deutschen Literatur vorhanden ist. Im ersten Teil widmet sich die vorliegende Arbeit de...
Vorgehensweisen innerhalb der FMEA-Arten
Schloske, Alexander; Mannuß, Oliver
2015-01-01
Die FMEA stellt heutzutage eines der wichtigsten Werkzeuge des präventiven Risikomanagements dar. Die universell anwendbare Vorgehensweise des VDA hat sich dabei in der Industrie etabliert. Der Beitrag beschreibt aus der Sicht von 25 Jahren FMEA-Erfahrung, wie die FMEA zielführend erstellt wird und mit welchen Tipps und Tricks eine effiziente und effektive FMEA-Erstellung ermöglicht wird. Es wird dabei detailliert dargestellt, wie innerhalb der einzelnen FMEA-Arten (System, Konstruktion, Proz...
Vorgehensweisen innerhalb der FMEA-Arten
Schloske, Alexander
2014-01-01
Die FMEA stellt heutzutage eines der wichtigsten Werkzeuge des präventiven Risikomanagements dar. Die universell anwendbare Vorgehensweise des VDA hat sich dabei in der Industrie etabliert. Der Beitrag beschreibt aus der Sicht von 25 Jahren FMEA-Erfahrung, wie die FMEA zielführend erstellt wird und mit welchen Tipps und Tricks eine effiziente und effektive FMEA-Erstellung ermöglicht wird. Es wird dabei detailliert dargestellt, wie innerhalb der einzelnen FMEA-Arten (System, Konstruktion, Proz...
Some formal problems in gauge theories
International Nuclear Information System (INIS)
Magpantay, J.A.
1980-01-01
The concerns of this thesis are the problems due to the extra degrees of freedom in gauge-invariant theories. Since gauge-invariant Lagrangians are singular, Dirac's consistency formalism and Fadeev's extension are first reviewed. A clarification on the origin of primary constraints is given, and some of the open problems in singular Lagrangian theory are discussed. The criteria in choosing a gauge, i.e., attainability, maintainability and Poincare invariance are summarized and applied to various linear gauges. The effects of incomplete removal of all gauge freedom on the criteria for gauge conditions are described. A simple example in point mechanics that contains some of the features of gauge field theories is given. Finally, we describe a method of constructing gauge-invariant variables in various gauge field theories. For the Abelian theory, the gauge-invariant, transverse potential and Dirac's gauge-invariant fermion field was derived. For the non-Abelian case we introduce a local set of basis vectors and gauge transformations are interpreted as rotations of the basis vectors introduced. The analysis leads to the reformulation of local SU(2) field theory in terms of path-dependent U(1) x U(1) x U(1). However, the analysis fails to include the matter fields as of now
Coulomb systems seen as critical systems: Finite-size effects in two dimensions
International Nuclear Information System (INIS)
Jancovici, B.; Manificat, G.; Pisani, C.
1994-01-01
It is known that the free energy at criticality of a finite two-dimensional system of characteristic size L has in general a term which behaves like log L as L → ∞; the coefficient of this term is universal. There are solvable models of two-dimensional classical Coulomb systems which exhibit the same finite-size correction (except for its sign) although the particle correlations are short-ranged, i.e., noncritical. Actually, the electrical potential and electrical field correlations are critical at all temperatures (as long as the Coulomb system is a conductor), as a consequence of the perfect screening property of Coulomb systems. This is why Coulomb systems have to exhibit critical finite-size effects
Investigations of direct and sequential Coulomb break-up of light ions
International Nuclear Information System (INIS)
Srivastava, D.K.; Basu, D.N.; Rebel, H.
1988-07-01
Coulomb dissociation of 6 Li in the field of 208 Pb at different energies via resonance and continuum levels is discussed in detail. Relations are given which can be used to directly relate the Coulomb break-up cross section to the astrophysical S-factor. Predictions for energy dependence and angular-distributions are given. The direct Coulomb break-up of 6 Li is found to be of the same order of magnitude as the sequential break-up at higher projectile energies. The effect to eleastic scattering can be accounted for by introducing a dynamic polarization potential. Predictions are given for the direct Coulomb dissociation of 26 MeV/nucleon 7 Li and 16 O incident on 208 Pb through dipole transitions to the continuum, and for 20 Ne via quadrupole transitions in similar experimental situations. (orig.) [de
Derivation of magnetic Coulomb's law for thin, semi-infinite solenoids
Kitano, Masao
2006-01-01
It is shown that the magnetic force between thin, semi-infinite solenoids obeys a Coulomb-type law, which corresponds to that for magnetic monopoles placed at the end points of each solenoid. We derive the magnetic Coulomb law from the basic principles of electromagnetism, namely from the Maxwell equations and the Lorentz force.
Energy Technology Data Exchange (ETDEWEB)
Jurik, A.G.; Egund, N. [The Department of Radiology R, Aarhus Kommunehospital (Denmark)
2004-03-01
Cross-sectional imaging techniques play a decisive role in identification, localization, and characterization of alterations in the sacroiliac joint during the early stage of seronegative spondylarthropathy (SpA). Although several studies showed that the diagnostic capabilities of MRI and CT are superior to those of conventional radiography, they have not yet become established and accepted as methods for evaluating the grade of ankylosing spondylitis (AS) in contrast to conventional radiography. The lack of acceptance for MRI and/or CT methods for evaluating and grading changes in the sacroiliac joint makes it difficult to include the results of these procedures in classifying the grade of SpA. Moreover, grading the changes in the sacroiliac joint in SpA with a method more sensitive than conventional radiography will be of prime importance in assessing treatment, e.g., the efficacy of new biological therapeutic agents directed against the tumor necrosis factor-alpha (TNF-{alpha}). An overview of the available grading methods is provided and MRI and CT techniques are presented. (orig.) [German] Schnittbildverfahren spielen bei der Identifizierung, Lokalisation und Charakterisierung von Veraenderungen des Sakroiliakalgelenks (SIG) im Fruehstadium der seronegativen Spondylarthropathie (SpA) eine entscheidende Rolle. Obwohl mehrere Studien zeigten, dass der diagnostische Wert der MRT und CT jenem der konventionellen Radiographie ueberlegen ist, hat sich das Schnittbildverfahren als Mittel zur Evaluierung des Grades der ankylosierenden Spondylitis (AS) im Gegensatz zur konventionellen Radiographie noch nicht etabliert und durchgesetzt. Dieses Fehlen eines akzeptierten MRT- und/oder CT-Verfahrens zur Evaluierung und zum Grading der Veraenderungen am SIG macht es schwierig, die Ergebnisse dieser Verfahren bei der Einstufung des Grades der AS-Veraenderungen und Erarbeitung von Diagnosekriterien fuer andere Formen der SpA einzubeziehen. Ausserdem wird das Grading der SIG
Inter-grain coupling and grain charge in dusty plasma Coulomb crystals
International Nuclear Information System (INIS)
Smith, M. A.; Goodrich, J.; Mohideen, U.; Rahman, H. U.; Rosenberg, M.; Mendis, D. A.
1998-01-01
We have studied the lattice structure and grain charge of dusty plasma Coulomb crystals formed in rectangular conductive grooves as a function of plasma temperature and density. The crystal appears to be made of mutually repulsive columns of grains confined by the walls of the groove. The columns are oriented along the direction of the electrode sheath electric field. A simple phenomenological model wherein the inter-grain spacing results from an attractive electric field induced dipole-dipole force balanced by a repulsive monopole Coulomb force is consistent with observed features of the Coulomb crystal
Diversität und Konvergenz an der Wurzel: Perspektiven der Romanistik in Zeiten der Globalisierung
Directory of Open Access Journals (Sweden)
Bernhard Teuber
2016-03-01
Full Text Available I. Wieder eine Studienreform – II. Diversitäten und Konvergenz – III. Die fetten Jahre der Theorie – IV. Was in Zukunft zu tun bleibt: 1.Digital Humanities; 2.Spatial Turn; 3.Postcolonial Studies; 4.Gender Studies; 5.Ethical Turn – V. Averroes auf der Suche
Directory of Open Access Journals (Sweden)
Jan Józef Janicki
2003-12-01
Full Text Available Im Jahr 2003 feiert die Kirche in Polen das 750-jährige Jubiläum der Heiligsprechung des Bischofs Stanislaus (1030-1079, der im Jahre 1253 in Assisi, als erste Pole, kanonisiert wurde und zum Patron von ganz Polen ernannt. Der Verfasser analisiert das Messformular und Stundengebetsformular von der liturgischen Feier des hl. Stanislaus, Bischof und Märtyrer am 8 Mai und sucht dadurch die Lehre (logos über das christliche Leben und die konkrete Lebens-Konsequenzen (etos aufzuzeigen. Die erneuerten liturgischen Texte der Gebete des neuen römischen Messbuches und des Stundengebetes zeigen den Glauben der betenden Kirche nach dem alten Prinzip: legem credendi lex statuat supplicandi (oder kurz ausgedrückt: lex orandi lex credendi. Der Zweck also des hier vorgestellten Artikels ist es, den Glauben der Kirche über das heilige Leben der Christen zu demonstrieren, welches uns eine Analyse der euchologischen Texte und der Texte der Wortliturgie ermöglicht. Der Verfasser benutzte dann die Möglichkeit, diese ganze Problematik im breiten theologisch-liturgischen und pastoralen Kontext darzustellen. Dabei benutzte er die Dokumente der Kirche der letzten Jahre, insbesondere die Lehre des II. Vatikanischen Konzils wenn es um den pastoralen Dienst der Bischöfe geht, dann die pastoral-theologischen Briefe des Papstes Pius XII und des Papstes Johannes Paul II, zum 700-jährigen und zum 750-jährigen Jubiläum der Kanonisation des hl. Bischofs Stanislaus. Es geht aber auch um alles das, was Johannes Paul II und früher als Kardinal Karol Wojtyła zum Jahrestag des Märtyrertodes geschrieben hat. Die liturgischen Gebetstexte lex orandi und die Wortliturgie unterstreichen in ihrer lex credendi, dass der hl. Stanislaus in seinem Leben, in seiner Zeit und seiner Kirche, den Auftrag und die Vollmacht - die Christus den Aposteln und ihren Nachfolgern gegeben hat - alle Völker zu lehren, die Menschen in der Wahrheit zu heiligen und sie zu weiden, verwirklicht
One-Step Direct Return Method For Mohr-Coulomb Plasticity
DEFF Research Database (Denmark)
Clausen, Johan; Damkilde, Lars; Andersen, Lars
2004-01-01
A new return method for the Mohr-Coulomb yield criteria is presented. The idea is to transform the problem into the principal direction and thereby achieve very simple formulas for calculating the elastic return stresses.......A new return method for the Mohr-Coulomb yield criteria is presented. The idea is to transform the problem into the principal direction and thereby achieve very simple formulas for calculating the elastic return stresses....
Energy Technology Data Exchange (ETDEWEB)
Uhl, M. [Universitaetsklinik Freiburg (Germany). Abt. fuer Radiologische Diagnostik; Allmann, K.H. [Universitaetsklinik Freiburg (Germany). Abt. fuer Radiologische Diagnostik; Hauer, M.P. [Universitaetsklinik Freiburg (Germany). Abt. fuer Radiologische Diagnostik; Laubenberger, J. [Universitaetsklinik Freiburg (Germany). Abt. fuer Radiologische Diagnostik; Kempis, J. v. [Universitaetsklinik Freiburg (Germany). Abt. fuer Rheumatologie und Klinische Immunologie; Langer, M. [Universitaetsklinik Freiburg (Germany). Abt. fuer Radiologische Diagnostik
1997-06-01
Nuclear magnetic resonance tomography (MRI) represents essential progress in the diagnostic means for evaluation of lesions of the muskuloskeletal system. The imaging of bone joints including material and structures like cartilage, tendons, ligaments, effusions, pannus, cortical bone and marrow offers essential advantages for diagnosis, differential diagnosis, follow-up control and detection of local complications in rheumatics radiology. The review article discusses the achievements of MRI for detection of early signs of rheumatoid arthritis and the current indications for MRI examination for early diagnosis. (Orig./AJ) [Deutsch] Die Magnetresonanztomographie (MRT) ist ein bedeutender Fortschritt in der Diagnostik von Erkrankungen des muskuloskelettalen Systems. Die Darstellung von Gelenkstrukturen einschliesslich Knorpel, Sehnen, Baendern, Erguessen, Pannus, kortikalem Knochen und Mark ist in der Diagnostik, Differentialdiagnostik, Verlaufsbeurteilung und der Aufdeckung von lokalen Komplikationen in der Rheumaradiologie von erheblichem Vorteil. In der Uebersicht werden die Fruehveraenderungen der rheumatoiden Arthritis in der MRT-Bildgebung und die heute aktuellen Indiakationen fuer den Einsatz der MRT in der Fruehdiagnostik diskutiert. (Orig./AJ)
Light-cone gauge versus proper-time gauge for massless spinning particles
International Nuclear Information System (INIS)
Skagerstam, B.S.; Stern, A.
1987-01-01
Although the light-cone gauge is convenient for many applications in physics, it is known to distort topology. We show that as a consequence, some interesting, possibly physical, features of a quantum theory may be missed when working in the light-cone gauge. We shall illustrate this by examining the description of massless spinning particles in an arbitrary number of space-time dimensions. When quantizing such particles in four space-time dimensions (without introducing Grassmann degrees of freedom), the light-cone gauge yields a purely bosonic spectrum, i.e. the helicity λ is integer-valued. The problem is rectified by going to the proper-time gauge; there λ = 0, ±1/2, ±1, ... Upon using the proper-time gauge to quantize massless particle systems in more than four space-time dimensions, we find the following interesting features: Except for space-time dimension d equal to 5 and 9, (i) wave functions cannot be expressed as global functions of momentum (or position). (This is also true for d=4.) Further, for d ≠ 5 and 9, (ii) the helicity group spin (d-2) and (iii) canonical position operators do not exist, globally. (The result that helicity cannot be globally defined resembles a known property of nonabelian monopoles arising in grand unified theories. There, topological obstructions prevent one from defining the color group, globally.) All of the features (i)-(iii) are missed when working in the light-cone gauge. (orig.)
Vogel, Marlene
2016-01-01
Der Umgang mit interaktiven Schnittstellen technischer Geräte gehört heute zum Alltag vieler Menschen. Diese Schnittstellen werden durch die zunehmende Funktionalität der Geräte komplexer. Beispielsweise sind die heutigen Mobiltelefone, sogenannte Smartphones, mit ihrer unterstützenden und umfangreichen Funktionalität nicht mehr aus dem Leben vieler Menschen wegzudenken. Dabei ist es nicht nur der effiziente Umgang mit der Technik, der u. a. für die Kaufentscheidung eine Bedeutung hat. Vielme...
Risiko Energiewende Wege aus der Sackgasse
Kleinknecht, Konrad
2015-01-01
Der Ausstieg aus der Nutzung der Kernenergie in Deutschland wurde im Sommer 2011 im Eiltempo beschlossen. Jetzt zeigt sich, dass es keinen realistischen Plan für den Umbau der Energieversorgung in der vorgesehenen Frist von zehn Jahren gibt. Für die Umstellung unserer gesamten Stromversorgung und damit unserer Wirtschaft ist der Zeitraum zu kurz. Es fehlt eine belastbare empirische Begründung, die Fragen der Versorgungssicherheit, der Finanzierbarkeit, der Auswirkungen auf die wirtschaftliche Entwicklung und die soziale Gerechtigkeit behandeln müsste. Somit droht diese Wende an ihren Widersprüchen zu scheitern. Konrad Kleinknecht versucht in seinem Buch, die Probleme zu benennen und Antworten zu finden. Für ihn stellen sich die folgenden Fragen: Welche Möglichkeit haben wir, mit Windkraft und Solarenergie einen Teil der Stromversorgung zu ersetzen? Welche Stromquellen bieten gesicherte Leistung? Können wir auf Kohlekraftwerke verzichten? Brauchen wir neue Stromtrassen? Wie lässt sich Strom speichern?...
Ustekinumab in der Therapie der Pustulosis palmoplantaris - Eine Fallserie mit neun Patienten.
Buder, Valeska; Herberger, Katharina; Jacobi, Arnd; Augustin, Matthias; Radtke, Marc Alexander
2016-11-01
Die Pustulosis palmoplantaris ist eine chronisch entzündliche Hauterkrankung, die mit bedeutenden Einschränkungen der Lebensqualität und der Belastbarkeit einhergeht. Aufgrund von Zulassungsbeschränkungen und einem häufig therapierefraktären Verlauf sind die Behandlungsmöglichkeiten limitiert. Nach zuvor frustranen Therapien erhielten 9 Patienten mit Pustulosis palmoplantaris nach Ausschluss einer latenten Tuberkulose Ustekinumab (45 mg Ustekinumab bei 100 kg KG) in Woche 0, 4, 12 und 24. Reguläre Visiten erfolgten nach 4 und 12 Wochen, im weiteren Verlauf alle 12 Wochen. Das Durchschnittsalter bei Therapiebeginn betrug 48 Jahre. Drei Patienten waren männlich. Bei n = 4 Patienten (44,4 %) wurde eine Verbesserung um 75 % des Palmoplantar-Psoriasis-Area-Severity-Index (PPPASI) erreicht. Insgesamt verbesserte sich der PPPASI nach 24 Wochen durchschnittlich um 71,6 %. Eine komplette Abheilung zeigte sich bei n = 2 Patienten nach 24 Wochen. Bis auf lokale Injektionsreaktionen und leichte Infekte wurden keine unerwünschten Wirkungen beobachtet. Die Fallserie ist ein weiterer Beleg für die Wirksamkeit und Verträglichkeit von Ustekinumab in der Therapie der Pustulosis palmoplantaris. Zur Beurteilung der Langzeitwirkung und -sicherheit sowie der Wirksamkeit einer intermittierenden Therapie sind kontrollierte Studiendaten sowie Beobachtungen im Rahmen von Patientenregistern notwendig. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.
Zur beruflichen Fortbildung der Musiklehrer in Lettland
Directory of Open Access Journals (Sweden)
Ligita Stramkale
2014-12-01
Full Text Available Die berufliche Fortbildung der Musiklehrer war in Lettland immer ein aktuelles Thema. Vorschriften des lettischen Ministerkabinetts bestimmen die Anforderungen der beruflichen Fortbildung der Lehrer. Diese werden bei der Durchführung vielfältiger Fortbildungsprogramme für die Musiklehrer umgesetzt. Im folgenden Beitrag werden die Besonderheiten der beruflichen Fortbildung der Musiklehrer und eines der Fortbildungsmodule – „Didaktische Modelle des Musikunterrichts“ – analysiert. Die hier referierte empirische Studie versucht, die Einstellungen der Musiklehrer zu den Einflussfaktoren auf die Qualität der beruflichen Fortbildungskurse und deren Lektoren zu erfassen. Als Ergebnis wird auf mehrere Faktoren hingewiesen, die auf die Qualität der beruflichen Fortbildungskurse der Musiklehrer Einfluss nehmen.
Przybytek, Michal; Helgaker, Trygve
2013-08-07
We analyze the accuracy of the Coulomb energy calculated using the Gaussian-and-finite-element-Coulomb (GFC) method. In this approach, the electrostatic potential associated with the molecular electronic density is obtained by solving the Poisson equation and then used to calculate matrix elements of the Coulomb operator. The molecular electrostatic potential is expanded in a mixed Gaussian-finite-element (GF) basis set consisting of Gaussian functions of s symmetry centered on the nuclei (with exponents obtained from a full optimization of the atomic potentials generated by the atomic densities from symmetry-averaged restricted open-shell Hartree-Fock theory) and shape functions defined on uniform finite elements. The quality of the GF basis is controlled by means of a small set of parameters; for a given width of the finite elements d, the highest accuracy is achieved at smallest computational cost when tricubic (n = 3) elements are used in combination with two (γ(H) = 2) and eight (γ(1st) = 8) Gaussians on hydrogen and first-row atoms, respectively, with exponents greater than a given threshold (αmin (G)=0.5). The error in the calculated Coulomb energy divided by the number of atoms in the system depends on the system type but is independent of the system size or the orbital basis set, vanishing approximately like d(4) with decreasing d. If the boundary conditions for the Poisson equation are calculated in an approximate way, the GFC method may lose its variational character when the finite elements are too small; with larger elements, it is less sensitive to inaccuracies in the boundary values. As it is possible to obtain accurate boundary conditions in linear time, the overall scaling of the GFC method for large systems is governed by another computational step-namely, the generation of the three-center overlap integrals with three Gaussian orbitals. The most unfavorable (nearly quadratic) scaling is observed for compact, truly three-dimensional systems
Translational groups as generators of gauge transformations
International Nuclear Information System (INIS)
Scaria, Tomy
2003-01-01
We examine the gauge generating nature of the translational subgroup of Wigner's little group for the case of massless tensor gauge theories and show that the gauge transformations generated by the translational group are only a subset of the complete set of gauge transformations. We also show that, just as in the case of topologically massive gauge theories, translational groups act as generators of gauge transformations in gauge theories obtained by extending massive gauge noninvariant theories by a Stueckelberg mechanism. The representations of the translational groups that generate gauge transformations in such Stueckelberg extended theories can be obtained by the method of dimensional descent. We illustrate these results with the examples of Stueckelberg extended first class versions of Proca, Einstein-Pauli-Fierz, and massive Kalb-Ramond theories in 3+1 dimensions. A detailed analysis of the partial gauge generation in massive and massless second rank symmetric gauge theories is provided. The gauge transformations generated by the translational group in two-form gauge theories are shown to explicitly manifest the reducibility of gauge transformations in these theories
Translational groups as generators of gauge transformations
Scaria, Tomy
2003-11-01
We examine the gauge generating nature of the translational subgroup of Wigner’s little group for the case of massless tensor gauge theories and show that the gauge transformations generated by the translational group are only a subset of the complete set of gauge transformations. We also show that, just as in the case of topologically massive gauge theories, translational groups act as generators of gauge transformations in gauge theories obtained by extending massive gauge noninvariant theories by a Stückelberg mechanism. The representations of the translational groups that generate gauge transformations in such Stückelberg extended theories can be obtained by the method of dimensional descent. We illustrate these results with the examples of Stückelberg extended first class versions of Proca, Einstein-Pauli-Fierz, and massive Kalb-Ramond theories in 3+1 dimensions. A detailed analysis of the partial gauge generation in massive and massless second rank symmetric gauge theories is provided. The gauge transformations generated by the translational group in two-form gauge theories are shown to explicitly manifest the reducibility of gauge transformations in these theories.
On the dynamics of gauge potential
International Nuclear Information System (INIS)
Tao Jiafu; Li Yuanjie; Zhang Jinru
1992-01-01
The gauge potential is resolved into gauge potential of strength and gauge potential of phase. The phase gauge potential can be described with an equivalent potential of inertial force. A Lagrangian density with phase gauge potential is given and some examples are discussed. The method proposed has been extended to the case of the non-Abelian group
Long-Range Coulomb Effect in Intense Laser-Driven Photoelectron Dynamics.
Quan, Wei; Hao, XiaoLei; Chen, YongJu; Yu, ShaoGang; Xu, SongPo; Wang, YanLan; Sun, RenPing; Lai, XuanYang; Wu, ChengYin; Gong, QiHuang; He, XianTu; Liu, XiaoJun; Chen, Jing
2016-06-03
In strong field atomic physics community, long-range Coulomb interaction has for a long time been overlooked and its significant role in intense laser-driven photoelectron dynamics eluded experimental observations. Here we report an experimental investigation of the effect of long-range Coulomb potential on the dynamics of near-zero-momentum photoelectrons produced in photo-ionization process of noble gas atoms in intense midinfrared laser pulses. By exploring the dependence of photoelectron distributions near zero momentum on laser intensity and wavelength, we unambiguously demonstrate that the long-range tail of the Coulomb potential (i.e., up to several hundreds atomic units) plays an important role in determining the photoelectron dynamics after the pulse ends.
Hybrid and Constrained Resolution-of-Identity Techniques for Coulomb Integrals.
Duchemin, Ivan; Li, Jing; Blase, Xavier
2017-03-14
The introduction of auxiliary bases to approximate molecular orbital products has paved the way to significant savings in the evaluation of four-center two-electron Coulomb integrals. We present a generalized dual space strategy that sheds a new light on variants over the standard density and Coulomb-fitting schemes, including the possibility of introducing minimization constraints. We improve in particular the charge- or multipole-preserving strategies introduced respectively by Baerends and Van Alsenoy that we compare to a simple scheme where the Coulomb metric is used for lowest angular momentum auxiliary orbitals only. We explore the merits of these approaches on the basis of extensive Hartree-Fock and MP2 calculations over a standard set of medium size molecules.
Calculation of proton-deuteron phase parameters including the Coulomb force
International Nuclear Information System (INIS)
Alt, E.O.; Sandhas, W.; Ziegelmann, H.
1985-04-01
A previously proposed exact method for including the Coulomb force in three-body collisions is applied to proton-deuteron scattering. We present phase shifts for angular momenta up to L=9, from elastic threshold to 50 MeV proton laboratory energy. Separable rank-one potentials are taken for the nuclear interactions. A charge-independent and a charge-symmetric choise, while leading to different neutron-deuteron and proton-deuteron phase parameters, nevertheless yields practically the same Coulomb corrections. We, moreover, investigate the question of P-wave resonances.A critical comparison of our results with those obtained in a co-ordinate space formalism is performed. Furthermore, proposals for an approximate inclusion of the Coulomb potential are tested, and found unsatisfactory. (orig.)
Gauge boson/Higgs boson unification: The Higgs bosons as superpartners of massive gauge bosons
International Nuclear Information System (INIS)
Fayet, P.
1984-01-01
We show how one can use massive gauge superfields to describe, simultaneously, gauge bosons (Wsup(+-), Z, ...) and Higgs bosons (wsup(+-), z, ...) together with their spin-1/2 partners (pairs of winos, zinos, ...), despite their different electroweak properties. This provides a manifestly supersymmetric formulation of spontaneously broken supersymmetric gauge theories, and makes explicit the relations between massive gauge bosons and Higgs bosons. It raises, however, the following question: if the gauge bosons Wsup(+-) and Z and the Higgs bosons wsup(+-) and z are related by supersymmetry, how it is possible that the former couple to leptons and quarks proportionately to g or g', and the latter proportionately to gsub(F)sup(1/2) m (fermions). The paradox is solved as follows: when the Higgs bosons are described by massive gauge superfields, the lagrangian density is non-polynomial and field redefinitions have to be performed, in particular: lepton or quark field -> lepton or quark field + (approx.= Gsub(F)sup(1/2) Higgs field) (lepton or quark field). They automatically regenerate, from the lepton and quark supersymmetric mass terms, the correct Yukawa couplings of Higgs bosons proportional to fermion masses. We also apply this method to the case in which an extra U(1) group is gauged, the standard Higgs boson h 0 being then the superpartner of the new neutral gauge boson U. (orig.)
Coulomb Final State Interactions for Gaussian Wave Packets
Wiedemann, Urs Achim; Heinz, Ulrich W
1999-01-01
Two-particle like-sign and unlike-sign correlations including Coulomb final state interactions are calculated for Gaussian wave packets emitted from a Gaussian source. We show that the width of the wave packets can be fully absorbed into the spatial and momentum space widths of an effective emission function for plane wave states, and that Coulomb final state interaction effects are sensitive only to the latter, but not to the wave packet width itself. Results from analytical and numerical calculations are compared with recently published work by other authors.
Physikalische Therapie der Beckenbodeninsuffizienz - Methodenvergleich
Directory of Open Access Journals (Sweden)
Bocker B
2002-01-01
Full Text Available Harninkontinenz wird von der Internationalen Gesellschaft für Kontinenz als soziales und hygienisches Problem durch unwillkürlichen Harnverlust definiert [1]. Um Aussagen über die Wirksamkeit einzelner Therapieformen in der Behandlung dieser Erkrankung treffen zu können, untersuchten wir 24 Patientinnen mit neuromuskulärer Beckenbodenschwäche sowie 24 männliche Patienten nach Prostatektomie. In einer kontrollierten, prospektiven Längsschnittstudie erhielten je 8 Patienten jeder Diagnosegruppe nach randomisierter Zuordnung eine Serie Elektrostimulation der Beckenbodenmuskulatur (ES, Biofeedbacktherapie (BF und EMG-getriggerte Elektrostimulation (EMG-ES in Kombination mit einer standardisierten Krankengymnastik (KG. Hauptzielparameter ist der Harninkontinenzgrad, Nebenzielparameter die Häufigkeit der Inkontinenzepisoden und Beckenbodenspannung, gemessen über den Oberflächen-EMG-Bereich. In bezug auf den Harninkontinenzgrad sind die Ergebnisse am Studienende bei Einsatz der Feedbackverfahren signifikant besser als nach isolierter Elektrostimulation. Durch BF sank der Harninkontinenzgrad nach Ingelmann-Sundberg im Mittelwert von Therapiebeginn bis zum Ende des Follow-up um 1,2; nach EMG-ES um 1,05. Passive ES führte zu einer Harninkontinenzreduktion um 0,36. In der Beeinflussung der Inkontinenzepisoden ist die bessere Wirkung der Biofeedbackverfahren im Follow-up gesichert (Häufigkeit / d von 2,5 auf 0,75 gegenüber einer Abnahme von 2,6 auf 1,9 infolge ES. Bezüglich des EMG-Bereiches zeigt die reine Elektrostimulation im Gegensatz zu den Feedback-gekoppelten Verfahren (Zunahme der Aktivität um 13,6 bzw. 12 µV keine Wirkung auf die Muskelaktivität. Bei isolierter Betrachtung der Diagnosegruppen führt reine Biofeedbackbehandlung bei den prostatektomierten Patienten zur Abnahme der Harninkontinenz über das Therapieende hinaus: MV = 2,0 bei SD = 0,17 zu Beginn auf MV = 0,7 bei SD = 0,14 zwölf Wochen nach Therapie. Dagegen hat EMG
Directory of Open Access Journals (Sweden)
Stanislas d’Ornano
2005-10-01
Full Text Available In heutiger Zeit den politischen Status der Kultur und der Kunst zu untersuchen setzt voraus, dass man ebenfalls drei Aspekte unserer Epoche in Betracht zieht. Wir haben die Orientierung verloren aufgrund des Widerspruchs zwischen der Vielfalt der Wege (Theorien, Lebensstile, Kunstrichtungen einerseits und der Vorstellung der Erreichung eines Ziels (das Ende der Geschichte, die vollkommene Gesellschaft andererseits. Wir erleben täglich die Situation einer zweifachen Instrumentalisierung, ...
Medienbildung in der Volksschule
Directory of Open Access Journals (Sweden)
Katharina Grubesic
2013-12-01
Full Text Available In dieser Untersuchung steht der Zusammenhang zwischen Schule und Medien in Bezug auf die Wertvorstellungen und Einstellungen der Akteure auf Grundlage des Habituskonzepts von Bourdieu sowie des Konzepts des medialen Habitus von Kommer und Biermann im Mittelpunkt. Die von den Lehrenden vorgelebten verinnerlichten Dispositionen im handlungsspezifischen Umgang mit unterschiedlichen Medien als auch der zu Grunde liegende „legitime Geschmack“, in dem sich diese Veranlagungen ausdrücken, sind hierbei bedeutsam. Die Rekonstruktion des medialen Habitus von LehrerInnen wird durch einen Vergleich zweier divergierender Unterrichtskonzeptionen mit der Methode der Videoanalyse erreicht. Das mediendidaktische Design, die Mediennutzung und die aktive Unterrichtsbeteiligung stellen die Analyseschwerpunkte dar, die der Beschreibung der verinnerlichten Dispositionen aufgrund der vorgelebten Haltungen und Wertvorstellungen dienen. Die anschließende relationierte Beobachtung ermöglicht es, in Anlehnung an die Habitustypen von Mutsch, die Differenzen und Gemeinsamkeiten der Unterrichtskonzepte sowie der daraus resultierenden Chancen und Schwierigkeiten im Unterricht zu verdeutlichen. This study attempts to show the correlation between school and media based on media habits, experiences and patterns of media usage of teachers and pupils in primary schools. As a theoretical framework, Bourdieu’s conception of habitus and the conception of media habitus of Kommer and Biermann are used to reconstruct the media habitus of primary school teachers in different educational settings. In this research, media habitus is understood as a combination of media economic capital, media activities, experience and preferences, values and attitudes of media in daily routine just as purposes and motives of media usage and educational intervention in family life. This work focuses on pointing out the relevance of teachers’ media habitus in different educational designs in
Unified approach to probing Coulomb effects in tunnel ionization for any ellipticity of laser light.
Landsman, A S; Hofmann, C; Pfeiffer, A N; Cirelli, C; Keller, U
2013-12-27
We present experimental data that show significant deviations from theoretical predictions for the location of the center of the electron momenta distribution at low values of ellipticity ε of laser light. We show that these deviations are caused by significant Coulomb focusing along the minor axis of polarization, something that is normally neglected in the analysis of electron dynamics, even in cases where the Coulomb correction is otherwise taken into account. By investigating ellipticity-resolved electron momenta distributions in the plane of polarization, we show that Coulomb focusing predominates at lower values of ellipticity of laser light, while Coulomb asymmetry becomes important at higher values, showing that these two complementary phenomena can be used to probe long-range Coulomb interaction at all polarizations of laser light. Our results suggest that both the breakdown of Coulomb focusing and the onset of Coulomb asymmetry are linked to the disappearance of Rydberg states with increasing ellipticity.
Energy Technology Data Exchange (ETDEWEB)
Einhaeupl, K.M. [Klinik und Poliklinik fuer Neurologie, Universitaetsklinikum Charite, Medizinische Fakultaet der Humboldt-Universitaet, Berlin (Germany); Valdueza, J.M. [Klinik und Poliklinik fuer Neurologie, Universitaetsklinikum Charite, Medizinische Fakultaet der Humboldt-Universitaet, Berlin (Germany)
1997-03-01
Today, the diagnostic and therapeutic principles in the management of stroke are changing. Prevention of stroke is one of the major fields of research. One important aim of the newly developed diagnostic techniques is the identification of a particular subgroup of patients with compromised cerebral circulation who will benefit from surgical or medical therapies. The assessment of the CVRC with tracer techniques and the acetazolamide test seem to be a realiable and promising method for this purpose: 1. In carotid artery occlusion, the measurement of CVRV facilitates the identification of a subgroup of patients with compromised CVRC who show an improvement of CVRC after EC-IC bypass surgery. The value of bypass surgery for the prevention of stroke however, has to be confirmed by prospective studies. 2. The benefit from carotid surgery for patients with high-grade carotid stenosis and transient ischemic attack has been convincingly demonstrated by several studies. In asymptomatic patients, however, desobliteration of the carotid artery remains controversial. The identification of asymptomatic cases with compromised CVRC probably contributes to the recognition of patients with a high risk of suffering hemodynamic stroke. 3. In vascular dementia, cerebral blood flow measurements at rest alone have not been useful. CVRC measurements may offer a diagnostic advance in this still not well understood disease. (orig.) [Deutsch] Die Erkennung von Patientengruppen mit besonderer Schlaganfallgefaehrdung, die von konservativen wie chirurgischen Massnahmen profitieren wuerden, ist von hoechster klinischer Relevanz. Mit der Bestimmung der zerebrovaskulaeren Reservekapazitaet (CVRC) mit Acetazolamid besitzen wir einen funktionellen Parameter der zerebralen Haemodynamik, der eine Risikoabschaetzung bezueglich eines Schlaganfalls fuer folgende Indikationen erwarten laesst: 1. Bei Patienten mit einem Karotisverschluss konnte von verschiedenen Arbeitsgruppen gezeigt werden, dass sich
Three-body Coulomb systems using generalized angular-momentum S states
Whitten, R. C.; Sims, J. S.
1974-01-01
An expansion of the three-body Coulomb potential in generalized angular-momentum eigenfunctions developed earlier by one of the authors is used to compute energy eigenvalues and eigenfunctions of bound S states of three-body Coulomb systems. The results for He, H(-), e(-)e(+)e(-), and pmu(-)p are compared with the results of other computational approaches.
Long-range terms in atomic collisions
International Nuclear Information System (INIS)
McGuire, J.H.; Weaver, O.L.
1986-01-01
Various separations, or ''gauge choices,'' are possible for the decomposition of the total Hamiltonian into electronic and internuclear terms. We show that, for one particular choice, all long-range Coulomb terms are associated with the internuclear motion. The potential then associated with electronic transitions is non-Coulombic. Some practical consequences of this gauge choice are discussed
Directory of Open Access Journals (Sweden)
Almeida DRP
2016-01-01
Full Text Available David RP Almeida,1 Eric K Chin,2,3 Shaival S Shah,3 Benjamin Bakall,3 Karen M Gehrs,3 H Culver Boldt,3 Stephen R Russell,3 James C Folk,3 Vinit B Mahajan3,41VitreoRetinal Surgery PA, Minneapolis, MN, 2Retina Consultants of Southern California, Riverside, CA, 3Vitreoretinal Service, Department of Ophthalmology and Visual Sciences, 4Omics Laboratory, University of Iowa, Iowa City, IA, USABackground: The role of pars plana vitrectomy (PPV for endophthalmitis has evolved over recent decades but the literature is lacking on comparisons between small-gauge and 20-gauge vitrectomy.Objective: To evaluate evolving etiological and microbiological trends in patients undergoing vitrectomy for endophthalmitis and to compare culture-positive rates and visual outcomes between small-gauge (23- and 25-gauge and 20-gauge instrumentation during vitrectomy for endophthalmitis.Methods: Ten-year retrospective comparative case series and prospective laboratory in vitro testing. Tertiary care academic referral center. Patients who underwent PPV for endophthalmitis between 2003 and 2013. Vitreous biopsies were obtained in all cases. The effect of vitrectomy gauge (20-, 23-, and 25-gauge and vitreous cutting rate (1,500 and 5,000 cuts per minute on the viability of bacterial culture was evaluated in an in vitro prospective laboratory investigation.Main outcome measures: Comparison of etiology, microbiology culture-positive rates, and visual outcomes between small-gauge and 20-gauge instrumentation in patients undergoing PPV for infectious endophthalmitis.Results: A total of 61 cases of vitrectomy for endophthalmitis were identified over a 10-year period; of these, 34 were treated with small-gauge (23- and 25-gauge vitrectomy and 27 were treated with 20-gauge vitrectomy. In the small-gauge group, 12 cases (35.3% yielded culture-positive results versus 20 cases (74.1% with culture positivity in the 20-gauge cohort (P=0.002. The most common cause of endophthalmitis was
International Nuclear Information System (INIS)
O'Raifeartaigh, L.
1979-01-01
This review describes the principles of hidden gauge symmetry and of its application to the fundamental interactions. The emphasis is on the structure of the theory rather than on the technical details and, in order to emphasise the structure, gauge symmetry and hidden symmetry are first treated as independent phenomena before being combined into a single (hidden gauge symmetric) theory. The main application of the theory is to the weak and electromagnetic interactions of the elementary particles, and although models are used for comparison with experiment and for illustration, emphasis is placed on those features of the application which are model-independent. (author)
Der digitalisierte Steuerpflichtige
Directory of Open Access Journals (Sweden)
Ehrke-Rabel, Tina
2017-12-01
Full Text Available Der digitalisierte Steuerpflichtige ist digitalisiert in seinem Wirtschaften und digitalisiert in seiner Interaktion mit der Finanzverwaltung. Digitale und digitalisierte Wirtschaftsmodelle stellen sowohl den Gesetzgeber als auch den Abgabenvollzug vor Herausforderungen, weil einerseits die physische Anknüpfung von Sachverhalten an staatliches Territorium nahezu unmöglich wird und andererseits staatliche Kontrolle von digitalen Wirtschaftsmodellen im derzeitigen System schwer möglich ist. Halten sich Steuerpflichtige an ihre Pflichten gegenüber der Finanzverwaltung, bietet die Digitalisierung jedoch Chancen für die Effizienzsteigerung des Vollzuges. Die Balance zwischen staatlicher Effizienz durch Digitalisierung und Schutz des Einzelnen vor übermäßigen Eingriffen in das Grundrecht auf Wahrung der Privatsphäre einerseits und dem Recht auf gute Verwaltung andererseits scheint derzeit jedoch noch nicht umfassend erreicht.
Multi-step contrast sensitivity gauge
Quintana, Enrico C; Thompson, Kyle R; Moore, David G; Heister, Jack D; Poland, Richard W; Ellegood, John P; Hodges, George K; Prindville, James E
2014-10-14
An X-ray contrast sensitivity gauge is described herein. The contrast sensitivity gauge comprises a plurality of steps of varying thicknesses. Each step in the gauge includes a plurality of recesses of differing depths, wherein the depths are a function of the thickness of their respective step. An X-ray image of the gauge is analyzed to determine a contrast-to-noise ratio of a detector employed to generate the image.
Jurco, B.; Schraml, S.; Schupp, P.; Wess, J.
2000-11-01
An enveloping algebra-valued gauge field is constructed, its components are functions of the Lie algebra-valued gauge field and can be constructed with the Seiberg-Witten map. This allows the formulation of a dynamics for a finite number of gauge field components on non-commutative spaces.