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1

Photon wave function is a controversial concept. Controversies stem from the fact that photon wave functions can not have all the properties of the Schroedinger wave functions of nonrelativistic wave mechanics. Insistence on those properties that, owing to peculiarities of photon dynamics, cannot be rendered, led some physicists to the extreme opinion that the photon wave function does not exist.

Iwo Bialynicki-Birula

2005-01-01

2

We argue that a photon wave function can be introduced if one is willing to redefine, in what we feel is a physically meaningful way, what one wishes to mean by such a wave function. The generation of a photon wave function by a spontaneously emitting atom is discussed.

J. E. Sipe

1995-01-01

3

NASA Astrophysics Data System (ADS)

We study the effect of final state dynamic correlation in single ionization of atoms by ion impact analyzing fully differential cross sections (FDCS). We use a distorted wave model where the final state is represented by a ?2 type correlated function, solution of a non-separable three body continuum Hamiltonian. This final state wave function partially includes the correlation of electron projectile and electron recoil relative motion as coupling terms of the wave equation. A comparison of fully differential results using this model with other theories and experimental data reveals that inclusion of dynamic correlation effects have little influence on FDCS, and do not contribute to a better description of available data in the case of electronic emission out-of scattering plane.

Ciappina, M. F.; Cravero, W. R.

2008-02-01

4

We review and sharpen the concept of a photon wave function based on the quantum theory of light. We argue that a point-like atom serves as the archetype for both the creation and detection of photons. Spontaneous emission from atoms provides a spatially localized source of photon states that serves as a natural wave packet basis for quantum states of

A. Muthukrishnan; M. O. Scully; M. S. Zubairy

2005-01-01

5

During the summer of 2003, record high temperatures were reported across Europe, causing thousands of casualties. Heat waves are sporadic recurrent events, characterised by intense and prolonged heat, associated with excess mortality and morbidity. The most frequent cause of death directly attributable to heat is heat stroke but heat waves are known to cause increases in all-cause mortality, specially circulatory and respiratory mortality. Epidemiological studies demonstrate excess casualties cluster in specific risk groups. The elderly, those with chronic medical conditions and the socially isolated are particularly vulnerable. Air conditioning is the strongest protective factor against heat-related disorders. Heat waves cause disease indirectly, by aggravating chronic disorders, and directly, by causing heat-related illnesses (HRI). Classic HRI include skin eruptions, heat cramps, heat syncope, heat exhaustion and heat stroke. Heat stroke is a medical emergency characterised by hyperthermia and central nervous system dysfunction. Treatment includes immediate cooling and support of organ-system function. Despite aggressive treatment, heat stroke is often fatal and permanent neurological damage is frequent in those who survive. Heat related illness and death are preventable through behavioural adaptations, such as use of air conditioning and increased fluid intake. Other adaptation measures include heat emergency warning systems and intervention plans and environmental heat stress reduction. Heat related mortality is expected to rise as a consequence of the increasing proportion of elderly persons, the growing urban population, and the anticipated increase in number and intensity of heat waves associated with global warming. Improvements in surveillance and response capability may limit the adverse health conditions of future heat waves. It is crucial that health professionals are prepared to recognise, prevent and treat HRI and learn to cooperate with local health agencies. PMID:16684487

Marto, Natália

2006-03-06

6

NSDL National Science Digital Library

The Ejs Wave Function Plotter model displays a one-dimensional wave function u(x,t) depicting a disturbance at position x and time t. The disturbance can be mass density, pressure, or electric field depending on the physical context. The default wave function is sinusoidal but any other analytic function can be entered in the text box. The number of sampling points can also be changed. You can modify this simulation if you have Ejs installed by right-clicking within the plot and selecting âOpen Ejs Modelâ from the pop-up menu item. Ejs Wave Function Plotter model was created using the Easy Java Simulations (Ejs) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double clicking the ejs_osc_chains_WaveFunctionPlotter.jar file will run the program if Java is installed. Ejs is a part of the Open Source Physics Project and is designed to make it easier to access, modify, and generate computer models. Additional Ejs models for Newtonian mechanics are available. They can be found by searching ComPADRE for Open Source Physics, OSP, or Ejs.

Christian, Wolfgang

2008-07-05

7

An analytical method is proposed for the dynamic response analysis of functionally graded thick hollow cylinders under impact\\u000a loading. The wave motion equation is solved using an analytical method that is based on the composition of Bessel functions.\\u000a The mechanical properties are considered as power functions of the radius across the thickness of FG cylinder. The FG cylinder\\u000a is excited

Seyed Mahmoud Hosseini; Mohammad Hossein Abolbashari

2010-01-01

8

The quantum state of a spatially closed universe can be described by a wave function which is a functional on the geometries of compact three-manifolds and on the values of the matter fields on these manifolds. The wave function obeys the Wheeler-DeWitt second-order functional differential equation. We put forward a proposal for the wave function of the ''ground state'' or

J. B. Hartle; S. W. Hawking

1983-01-01

9

We derive explicit expressions for the Wigner function of wave functions in D dimensions which depend on the hyperradius--that is, of s waves. They are based either on the position or the momentum representation of the s wave. The corresponding Wigner function depends on three variables: the absolute value of the D-dimensional position and momentum vectors and the angle between them. We illustrate these expressions by calculating and discussing the Wigner functions of an elementary s wave and the energy eigenfunction of a free particle.

Dahl, J. P. [Chemical Physics, Department of Chemistry, Technical University of Denmark, DTU 207, DK-2800 Lyngby (Denmark); Institut fuer Quantenphysik, Universitaet Ulm, D-89069 Ulm (Germany); Varro, S. [Research Institute for Solid State Physics and Optics, H-1525 Budapest, P.O. Box 49, (Hungary); Institut fuer Quantenphysik, Universitaet Ulm, D-89069 Ulm (Germany); Wolf, A.; Schleich, W. P. [Institut fuer Quantenphysik, Universitaet Ulm, D-89069 Ulm (Germany)

2007-05-15

10

Wave-function functionals for the density

NASA Astrophysics Data System (ADS)

We extend the idea of the constrained-search variational method for the construction of wave-function functionals ?[?] of functions ?. The search is constrained to those functions ? such that ?[?] reproduces the density ?(r) while simultaneously leading to an upper bound to the energy. The functionals are thereby normalized and automatically satisfy the electron-nucleus coalescence condition. The functionals ?[?] are also constructed to satisfy the electron-electron coalescence condition. The method is applied to the ground state of the helium atom to construct functionals ?[?] that reproduce the density as given by the Kinoshita correlated wave function. The expectation of single-particle operators W=?irin, n=-2,-1,1,2, W=?i?(ri) are exact, as must be the case. The expectations of the kinetic energy operator W=-(1)/(2)?i?i2, the two-particle operators W=?nun, n=-2,-1,1,2, where u=|ri-rj|, and the energy are accurate. We note that the construction of such functionals ?[?] is an application of the Levy-Lieb constrained-search definition of density functional theory. It is thereby possible to rigorously determine which functional ?[?] is closer to the true wave function.

Slamet, Marlina; Pan, Xiao-Yin; Sahni, Viraht

2011-11-01

11

NASA Astrophysics Data System (ADS)

This chapter summarizes the solutions of the one-electron nonrelativistic Schrödinger equation, and the one-electron relativistic Dirac equation, for the Coulomb potential. The standard notations and conventions used in the mathematics literature for special functions have been chosen in preference to the notations customarily used in the physics literature whenever there is a conflict. This has been done to facilitate the use of standard reference works such as Abramowitz and Stegun [9.1], the Bateman project [9.2,3], Gradshteyn and Ryzhik [9.4], Jahnke and Emde [9.5], Luke [9.6,7], Magnus, Oberhettinger, and Soni [9.8], Olver [9.9], Szego [9.10], and the new NIST Digital Library of Mathematical Functions project, which is preparing a hardcover update [9.11] of Abramowitz and Stegun [9.1] and an online digital library of mathematical functions [9.12]. The section on special functions contains many of the formulas which are needed to check the results quoted in the previous sections, together with a number of other useful formulas. Itincludes a brief introduction to asymptotic methods.

Hill, Robert

12

Multiphoton wave function after Kerr interaction

The multiphoton wave function after Kerr interaction is obtained analytically for an arbitrary photon number. The wave function is composed of two fundamental functions: the input mode function and the linear response function. The nonlinear effects appearing in this wave function are evaluated quantitatively, revealing the limitations of nonlinear quantum optics theories based on single-mode approximations.

Kazuki Koshino

2008-01-01

13

Wave-function functionals for the density

We extend the idea of the constrained-search variational method for the construction of wave-function functionals {psi}[{chi}] of functions {chi}. The search is constrained to those functions {chi} such that {psi}[{chi}] reproduces the density {rho}(r) while simultaneously leading to an upper bound to the energy. The functionals are thereby normalized and automatically satisfy the electron-nucleus coalescence condition. The functionals {psi}[{chi}] are also constructed to satisfy the electron-electron coalescence condition. The method is applied to the ground state of the helium atom to construct functionals {psi}[{chi}] that reproduce the density as given by the Kinoshita correlated wave function. The expectation of single-particle operators W={Sigma}{sub i}r{sub i}{sup n}, n=-2,-1,1,2, W={Sigma}{sub i}{delta}(r{sub i}) are exact, as must be the case. The expectations of the kinetic energy operator W=-(1/2){Sigma}{sub i}{nabla}{sub i}{sup 2}, the two-particle operators W={Sigma}{sub n}u{sup n}, n=-2,-1,1,2, where u=|r{sub i}-r{sub j}|, and the energy are accurate. We note that the construction of such functionals {psi}[{chi}] is an application of the Levy-Lieb constrained-search definition of density functional theory. It is thereby possible to rigorously determine which functional {psi}[{chi}] is closer to the true wave function.

Slamet, Marlina; Pan Xiaoyin; Sahni, Viraht [Sacred Heart University, Fairfield, Connecticut 06825 (United States); Faculty of Science, Ningbo University, 315211 Ningbo (China); Brooklyn College and The Graduate School of the City University of New York, New York, New York 10016 (United States)

2011-11-15

14

Estimation of wave source position by using spherical wave function

Estimation of wave source position is important technique for searching unknown noise source in EMI and EMC measurement. In this paper a new estimation technique for searching the position of wave source is proposed by using spherical vector wave function and point matching method. In our method a few virtual boundaries are placed on surrounding space encompassed the unknown wave

Kuniyuki Motojima; Hiroyuki Sutoh

2009-01-01

15

Dirac wave functions in nuclear distorted-wave calculations

A distorted-wave formulation of simple direct nuclear reactions, using Dirac wave functions, is presented. The resulting amplitude contains interior damping due to relativistic Darwin terms. The calculations are compared with standard Schroedinger results and significant differences are found.

Rost, E.; Shepard, J.R.; Murdock, D.

1982-08-16

16

Photon wave function and Zitterbewegung

In terms of a photon wave function corresponding to the (1,0)+(0,1) representation of the Lorentz group, the radiation and Coulomb fields within a source-free region can be described unitedly by a Lorentz-covariant Dirac-like equation. In our formalism, the relation between the positive- and negative-energy solutions of the Dirac-like equation corresponds to the duality between the electric and magnetic fields, rather

Zhi-Yong Wang; Cai-Dong Xiong; Qi Qiu

2009-01-01

17

Meson wave function from holographic approaches

We discuss the light-front wave function for the valence quark state of mesons using the AdS/CFT correspondence. We consider two kinds of wave functions obtained in different holographic Soft-Wall approaches.

Vega, Alfredo; Schmidt, Ivan [Departamento de Fisica y Centro de Estudios Subatomicos, Universidad Tecnica Federico Santa Maria, Casilla 110-V, Valparaiso (Chile); Branz, Tanja; Gutsche, Thomas; Lyubovitskij, Valery E. [Institut fuer Theoretische Physik, Universitaet Tuebingen, Kepler Center for Astro and Particle Physics, Auf der Morgenstelle 14, D-72076 Tuebingen (Germany)

2010-08-04

18

Wave impact pressures on vertical cylinders

Laboratory measurements of the pressure distributions on surface-piercing vertical cylinders due to breaking waves are presented. Breaking waves are generated in a repeatable fashion under program control, and both vertical and azimuthal distributions of pressures were measured over many repeats of the experiments. Despite the repeatability of the controllable experimental conditions, it is found that the highest impact pressures are

D. Zhou; E. S. Chan; W. K. Melville

1991-01-01

19

The destructive impact of the rogue waves

NASA Astrophysics Data System (ADS)

In our talk rogue waves at the ocean will be considered. By means of numerical modeling dangerous impact of rogue waves on the ships and oil rigs is calculated. Cases when these waves can bring in accident are considered. Using statistics of emergence of waves (see [1]-[2]), it is possible to estimate risks in each case. These results can be used for safety of the ships and oil rigs from rogue waves. References [1] V.E. Zakharov, A.I. Dyachenko, R.V. Shamin. How probability for freak wave formation can be found // THE EUROPEAN PHYSICAL JOURNAL - SPECIAL TOPICS Volume 185, Number 1, 113-124, DOI: 10.1140/epjst/e2010-01242-y [2] V.E. Zakharov, R.V. Shamin. Statistics of rogue waves in computer experiments // JETP Letters, 2012, V. 96, Issue 1, pp 66-69.

Shamin, Roman

2013-04-01

20

LOCAL RESONANCE INDUCED WAVE FUNCTIONAL MATERIALS

Wave functional materials denote a class of artificial materials that possess the ability to manipulate electromagnetic and elastic waves. Photonic and phononic crystals are examples of wave functional materials. In this talk, I start by introducing briefly the concept of Bragg scattering-based photonic and phononic crystals (1-6) that have been extensively studied during the past decade, followed by a description

Ping Sheng

21

Metastability and divergent wave functions

Metastable states of quantum systems can be evaluated as complex-valued eigensolutions of the time-independent Schroedinger equation if complex boundary conditions are applied. Such resonance boundary conditions have been formulated in the early days of quantum mechanics but few calculations have actually been performed utilizing this concept because the corresponding wave functions diverge asymptotically. Recent advances in the computation of energies and widths of metastable states will be discussed when Siegert boundary conditions are applied in order to achieve the necessary analytic continuation onto the complex energy plane as well as schemes to sidestep the divergencies altogether. Examples including potential resonances and multiply excited electronic states of atoms and ions illustrate the wide applicability of this approach.

Winkler, P. [Univ. of Nevada, Reno, NV (United States)

1993-04-01

22

Impact produced stress waves in composites

The Nonhomogenized Dynamic Method of Cells (NHDMOC) is used to study the propagation of stress waves through laminates. The accuracy of the theory is tested by applying it to a plate-impact experiment and checking its ability to resolve a propagation shock wave front. The theory is then compared to Lagrangian hydrodynamic calculations, where it is found that the NHDMOC consistently requires less fine spatial and temporal grids, and less artificial viscosity to control numerical noise. The theory is then used to treat the impact of an epoxy-graphite bilaminate. When the viscoelastic properties of the epoxy are accounted for, the theory agrees well with the experiment.

Clements, B.; Johnson, J.; Addessio, F.; Hixson, R.

1997-05-01

23

Modeling wave impact on salt marsh boundaries

NASA Astrophysics Data System (ADS)

Wind-wave attack is the fundamental cause of erosion of salt marsh boundaries. Tidal forcing acts as a proxy determining at which elevation waves pound against the marsh edge and conditioning the propagation and transformation of wave trains as they move toward these boundaries. The objective of the present work is to evaluate, through analysis of the results of a numerical model, the effect of wave action on marsh boundaries as a function of tidal elevation and wave height for different edge configurations. In order to link numerical simulations to field conditions, the model inputs are based on topographical and hydrodynamical surveys conducted at a study site at the Virginia Coast Reserve (VCR), VA. Model results show that the wave thrust on the marsh scarp strongly depends on tidal level. The thrust increases with tidal elevation until the marsh is submerged and then rapidly decreases. The wave thrust is maximum for a vertical scarp and minimum for a terraced scarp. Similarly, wave energy dissipation is maximized just above the marsh platform elevation, when wave reflection is reduced and wave breaking occurs at the marsh edge.

Tonelli, Mara; Fagherazzi, Sergio; Petti, Marco

2010-09-01

24

On the Wave Function of the Photon

It is shown that the wave function of the photon is a very useful concept with interesting ramifi- cations. It plays a major role in bridging the gap between classical theory of electromagnetism and quantum electrodynamics. The photon wave function can also be used to construct a phase-space distribution for the photon (Wigner function) that describes the transport of radiation.

Iwo Bialynicki-Birula

25

Stress Wave Source Characterization: Impact, Fracture, and Sliding Friction

NASA Astrophysics Data System (ADS)

Rapidly varying forces, such as those associated with impact, rapid crack propagation, and fault rupture, are sources of stress waves which propagate through a solid body. This dissertation investigates how properties of a stress wave source can be identified or constrained using measurements recorded at an array of sensor sites located far from the source. This methodology is often called the method of acoustic emission and is useful for structural health monitoring and the noninvasive study of material behavior such as friction and fracture. In this dissertation, laboratory measurements of 1--300 mm wavelength stress waves are obtained by means of piezoelectric sensors which detect high frequency (10 kHz--3MHz) motions of a specimen's surface, picometers to nanometers in amplitude. Then, stress wave source characterization techniques are used to study ball impact, drying shrinkage cracking in concrete, and the micromechanics of stick-slip friction of Poly(methyl methacrylate) (PMMA) and rock/rock interfaces. In order to quantitatively relate recorded signals obtained with an array of sensors to a particular stress wave source, wave propagation effects and sensor distortions must be accounted for. This is achieved by modeling the physics of wave propagation and transduction as linear transfer functions. Wave propagation effects are precisely modeled by an elastodynamic Green's function, sensor distortion is characterized by an instrument response function, and the stress wave source is represented with a force moment tensor. These transfer function models are verified though calibration experiments which employ two different mechanical calibration sources: ball impact and glass capillary fracture. The suitability of the ball impact source model, based on Hertzian contact theory, is experimentally validated for small (˜1 mm) balls impacting massive plates composed of four different materials: aluminum, steel, glass, and PMMA. Using this transfer function approach and the two mechanical calibration sources, four types of piezoelectric sensors were calibrated: three commercially available sensors and the Glaser-type conical piezoelectric sensor, which was developed in the Glaser laboratory. The distorting effects of each sensor are modeled using autoregressive-moving average (ARMA) models, and because vital phase information is robustly incorporated into these models, they are useful for simulating or removing sensor-induced distortions, so that a displacement time history can be retrieved from recorded signals. The Glaser-type sensor was found to be very well modeled as a unidirectional displacement sensor which detects stress wave disturbances down to about 1 picometer in amplitude. Finally, the merits of a fully calibrated experimental system are demonstrated in a study of stress wave sources arising from sliding friction, and the relationship between those sources and earthquakes. A laboratory friction apparatus was built for this work which allows the micro-mechanisms of friction to be studied with stress wave analysis. Using an array of 14 Glaser-type sensors, and precise models of wave propagation effects and the sensor distortions, the physical origins of the stress wave sources are explored. Force-time functions and focal mechanisms are determined for discrete events found amid the "noise" of friction. These localized events are interpreted to be the rupture of micrometer-sized contacts, known as asperities. By comparing stress wave sources from stick-slip experiments on plastic/plastic and rock/rock interfaces, systematic differences were found. The rock interface produces very rapid (<1 microsecond) implosive forces indicative of brittle asperity failure and fault gouge formation, while rupture on the plastic interface releases only shear force and produces a source more similar to earthquakes commonly recorded in the field. The difference between the mechanisms is attributed to the vast differences in the hardness and melting temperatures of the two materials, which affect the distribution of asp

McLaskey, Gregory Christofer

26

The impact of heat waves on mortality

Background Heat waves have been linked with an increase in mortality, but the associated risk has been only partly characterized. Methods We examined this association by decomposing the risk for temperature into a “main effect” due to independent effects of daily high temperatures, and an “added” effect due to sustained duration of heat during waves, using data from 108 communities in USA during 1987-2000. We adopted different definitions of heat-wave days based on combinations of temperature thresholds and days of duration. The main effect was estimated through distributed lag non-linear functions of temperature, which account for non-linear delayed effects and short-time harvesting. We defined the main effect as the relative risk between the median city-specific temperature during heat-wave days and the 75th percentile of the year-round distribution. The added effect was defined first using a simple indicator, and then a function of consecutive heat-wave days. City-specific main and added effects were pooled through univariate and multivariate meta-analytic techniques. Results The added wave effect was small (0.2%-2.8% excess relative risk, depending on wave definition) compared with the main effect (4.9%-8.0%), and was apparent only after 4 consecutive heat wave days. Conclusions Most of the excess risk with heat waves in the USA can be simply summarized as the independent effects of individual days’ temperatures. A smaller added effect arises in heat waves lasting more than 4 days.

Gasparrini, Antonio; Armstrong, Ben

2012-01-01

27

Spatial wave functions of photon and electron

The quantum mechanical model of the photon and electron is considered. The photon is conceived of as a particle moving with the speed of light which is accompanied by the wave function of the photon spreading out with an infinite speed. The wave function of the electron is introduced in terms of virtual photons tied to the electron. A description

D. L. Khokhlov

2010-01-01

28

Physical meaning of the photon wave function

Recently, the author [Phys. Rev. A 49, 2839 (1994)] proposed a quantum-mechanical theory of a photon, in which negative energy states can be dismissed from physical photon states without causing any difficulties. In this Brief Report the physical meaning of a photon wave function is investigated more precisely. The interpretation of a photon wave function as a probability amplitude is

Toshio Inagaki

1998-01-01

29

Meson wave function from holographic models

We consider the light-front wave function for the valence quark state of mesons using the AdS/CFT correspondence, as has been suggested by Brodsky and Teramond. Two kinds of wave functions, obtained in different holographic Soft-Wall models, are discussed.

Vega, Alfredo; Schmidt, Ivan [Departamento de Fisica y Centro de Estudios Subatomicos, Universidad Tecnica Federico Santa Maria, Casilla 110-V, Valparaiso (Chile); Branz, Tanja; Gutsche, Thomas; Lyubovitskij, Valery E. [Institut fuer Theoretische Physik, Universitaet Tuebingen, Kepler Center for Astro and Particle Physics, Auf der Morgenstelle 14, D-72076 Tuebingen (Germany)

2009-09-01

30

Exponentially self-similar impact ionization waves

The existence of generalized self-similar solutions to the system of continuity and Poisson equations is analyzed for the problem of evolution of impact ionization waves (IIWs). It is shown that, for any physically reasonable electric-field dependence of the impact ionization coefficients, there exist only exponentially self-similar ('limiting') asymptotic solutions. These solutions describe IIWs whose spatial scales and propagation velocities increase exponentially with time. Conditions are found for the existence of plane, cylindrical, and spherical waves of this type; their structure is described; analytical relations between the key parameters are derived; and effects of recombination (or attachment) and tunnel ionization are analyzed. It is shown that these IIWs are intermediate asymptotics of numerical solutions to the corresponding Cauchy problems. The most important and interesting type of exponentially self-similar IIWs are streamers in a uniform electric field. The simplest comprehensive and explicit model describing their evolution is a spherical IIW.

Kyuregyan, A. S., E-mail: ask@vei.r [All-Russia Institute of Electrical Engineering (Russian Federation)

2010-04-15

31

Spatial wave functions of photon and electron

The quantum mechanical model of the photon and electron is considered. The photon is conceived of as a particle moving with the speed of light which is accompanied by the wave function of the photon spreading out with an infinite speed. The wave function of the electron is introduced in terms of virtual photons tied to the electron. A description of electrostatic and magnetostatic interactions is given through the wave functions of electrons. The approach provides an explanation of the results of recent experiments measuring the speed of propagation of the bound magnetic field.

Khokhlov, D. L. [Sumy State University, R.-Korsakov St. 2, Sumy 40007 (Ukraine)

2010-12-01

32

On single nucleon wave functions in nuclei

The strong and singular interaction between nucleons, makes the nuclear many body theory very complicated. Still, nuclei exhibit simple and regular features which are simply described by the shell model. Wave functions of individual nucleons may be considered just as model wave functions which bear little resemblance to the real ones. There is, however, experimental evidence for the reality of single nucleon wave functions. There is a simple method of constructing such wave functions for valence nucleons. It is shown that this method can be improved by considering the polarization of the core by the valence nucleon. This gives rise to some rearrangement energy which affects the single valence nucleon energy within the nucleus.

Talmi, Igal [Weizamnn Institute of Science, Rehovot 76100 (Israel)

2011-05-06

33

The Wave Function and Quantum Reality

We investigate the meaning of the wave function by analyzing the mass and charge density distributions of a quantum system. According to protective measurement, a charged quantum system has effective mass and charge density distributing in space, proportional to the square of the absolute value of its wave function. In a realistic interpretation, the wave function of a quantum system can be taken as a description of either a physical field or the ergodic motion of a particle. The essential difference between a field and the ergodic motion of a particle lies in the property of simultaneity; a field exists throughout space simultaneously, whereas the ergodic motion of a particle exists throughout space in a time-divided way. If the wave function is a physical field, then the mass and charge density will be distributed in space simultaneously for a charged quantum system, and thus there will exist gravitational and electrostatic self-interactions of its wave function. This not only violates the superposition principle of quantum mechanics but also contradicts experimental observations. Thus the wave function cannot be a description of a physical field but be a description of the ergodic motion of a particle. For the later there is only a localized particle with mass and charge at every instant, and thus there will not exist any self-interaction for the wave function. It is further argued that the classical ergodic models, which assume continuous motion of particles, cannot be consistent with quantum mechanics. Based on the negative result, we suggest that the wave function is a description of the quantum motion of particles, which is random and discontinuous in nature. On this interpretation, the square of the absolute value of the wave function not only gives the probability of the particle being found in certain locations, but also gives the probability of the particle being there. The suggested new interpretation of the wave function provides a natural realistic alternative to the orthodox interpretation, and it also implies that the de Broglie-Bohm theory and many-worlds interpretation are wrong and the dynamical collapse theories are in the right direction by admitting wavefunction collapse.

Gao Shan [Unit for History and Philosophy of Science and Centre for Time, SOPHI, University of Sydney, Sydney, NSW 2006 (Australia)

2011-03-28

34

Wave-Functions of Small Quantum Clusters

Clusters of sizes ranging from two to five atoms are studied by variational quantum Monte Carlo techniques. A general form of trial wave-function is developed for which the variational bias is considerably smaller than the statistical error of currently available diffusion Monte Carlo estimates. The trial functions are designed by a careful analysis of long - and short-range behavior as

Andrei M. Mushinski

1995-01-01

35

Mass criterion for wave controlled impact response of composite plates

Impact duration strongly influences the impact response of plates. Long impacts cause a quasi-static response influenced by the plate size and boundary conditions. Short impacts cause a response governed by wave propagation unaffected of plate size and boundary conditions. This paper shows that the response type is governed by the impactor–plate mass ratio and not by impact velocity and derives

R. Olsson

2000-01-01

36

Convergence of Expansions of Continuum Functions on Resonance Wave Functions.

National Technical Information Service (NTIS)

The convergence of the expansions of the continuum wave function psisub(l)sup(+) (kx) and of the Green function Gsub(l)sup(+)(k, x, x') for x, x'in the interval (O, a) is studied. The resonance functions are solutions of the eigenvalue problem for the rad...

G. S. Kazacha

1984-01-01

37

Nonlinear wave function expansions : a progress report.

Some recent progress is reported for a novel nonlinear expansion form for electronic wave functions. This expansion form is based on spin eigenfunctions using the Graphical Unitary Group Approach and the wave function is expanded in a basis of product functions, allowing application to closed and open shell systems and to ground and excited electronic states. Each product basis function is itself a multiconfigurational expansion that depends on a relatively small number of nonlinear parameters called arc factors. Efficient recursive procedures for the computation of reduced one- and two-particle density matrices, overlap matrix elements, and Hamiltonian matrix elements result in a very efficient computational procedure that is applicable to very large configuration state function (CSF) expansions. A new energy-based optimization approach is presented based on product function splitting and variational recombination. Convergence of both valence correlation energy and dynamical correlation energy with respect to the product function basis dimension is examined. A wave function analysis approach suitable for very large CSF expansions is presented based on Shavitt graph node density and arc density. Some new closed-form expressions for various Shavitt Graph and Auxiliary Pair Graph statistics are presented.

Shepard, R.; Minkoff, M.; Brozell, S. R.; Chemistry

2007-12-01

38

Optimization of nonlinear wave function parameters.

An energy-based optimization method is presented for our recently developed nonlinear wave function expansion form for electronic wave functions. This expansion form is based on spin eigenfunctions, using the graphical unitary group approach (GUGA). The wave function is expanded in a basis of product functions, allowing application to closed-shell and open-shell systems and to ground and excited electronic states. Each product basis function is itself a multiconfigurational function that depends on a relatively small number of nonlinear parameters called arc factors. The energy-based optimization is formulated in terms of analytic arc factor gradients and orbital-level Hamiltonian matrices that correspond to a specific kind of uncontraction of each of the product basis functions. These orbital-level Hamiltonian matrices give an intuitive representation of the energy in terms of disjoint subsets of the arc factors, they provide for an efficient computation of gradients of the energy with respect to the arc factors, and they allow optimal arc factors to be determined in closed form for subspaces of the full variation problem. Timings for energy and arc factor gradient computations involving expansion spaces of > 10{sup 24} configuration state functions are reported. Preliminary convergence studies and molecular dissociation curves are presented for some small molecules.

Shepard, R.; Minkoff, M.; Chemistry

2006-01-01

39

Wave function shredding by sparse quantum barriers

NASA Astrophysics Data System (ADS)

We discuss the quantum motion of a particle passing through /? potentials arranged with increasing sparseness. For infinitely many barriers we derive conditions, expressed in terms ergodicity of wave-function phases, which ensure the purely singularly continuous spectrum. For a finite number of barriers, this is shown to translate into the quantum irregular scattering with fluctuations in all scales.

Cheon, T.; Exner, P.; Šeba, P.

2000-11-01

40

Does consciousness really collapse the wave function?

An analysis has been performed of the theories and postulates advanced by von Neumann, London and Bauer, and Wigner, concerning the role that consciousness might play in the collapse of the wave function, which has become known as the measurement problem. This reveals that an error may have been made by them in the area of biology and its interface

Fred H. Thaheld

2005-01-01

41

QMC simulations using backflow correlated wave functions

An inhomogeneous backflow transformation for many-particle wave functions is presented and applied to electrons in atoms, molecules, and solids. Backflow transformations are compact parametrizations, by which we mean that the number of parameters required to retrieve a given fraction of the correlation energy increases only slowly with system size. We report variational and diffusion quantum Monte Carlo (VMC and DMC)

Richard Needs

2007-01-01

42

The Maxwell wave function of the photon

James Clerk Maxwell unknowingly discovered a correct relativistic, quantum theory for the light quantum, forty-three years before Einstein postulated the photon's existence. In this theory, the usual Maxwell field is the quantum wave function for a single photon. When the non-operator Maxwell field of a single photon is second quantized, the standard Dirac theory of quantum optics is obtained. Recently,

M. G. Raymer; Brian J. Smith

2006-01-01

43

Impact damage detection in composite structures using Lamb waves

NASA Astrophysics Data System (ADS)

This paper is concerned with the detection of low velocity impact and the associated internal damage in composite structures using Lamb waves. Impact tests are carried out on a cross ply graphite epoxy plate using an instrumented impact testing system. The contact force and the surface motion caused by the impact load are recorded at several points on the plate surface away from the impact location and are analyzed based on theoretical simulations. The Lamb waves generated by the impact load and internal damage to the plate caused by it are shown to be highly effective tools for damage detection in laboratory specimens. Ultrasonic and impact tests are also conducted on a stiffened, woven composite panel in an effort to examine the propagation characteristics of ultrasonic waves in realistic composite structural components. Preliminary analysis of the recorded waveforms indicates that Lamb waves can be used to interrogate relatively large composite structures.

Mal, Ajit K.; Shih, Frank J.; Ricci, Fabrizio; Banerjee, Sauvik

2005-05-01

44

Laboratory study of plunging wave impacts on vertical cylinders

The characteristics of pressures associated with plunging wave impacts on a vertical cylinder are presented. Despite a high variability in the peak pressures, spatial distributions of the impact pressure time histories, both in the vertical direction and around the seaward front of the cylindrical surface, are found to vary systematically for a range of cylinder locations in the wave plunging

Eng-Soon Chan; Hin-Fatt Cheong; Boon-Cheng Tan

1995-01-01

45

Stream function solutions for steady water waves

NASA Astrophysics Data System (ADS)

Two stream function solutions for steady two-dimensional water waves are reviewed. The algorithm developed by DALRYMPLE (1974, Proc. 6th Conf. Offshore Tech., pp. 843 856) and used by HUDSPETH and SLOTTA (1978, Proceedings of the American Society of Civil Engineers,104, 319 334) is compared with the algorithm developed by CHAPLIN (1980, Coastal Engineering,3, 179 205). By examining more closely the near-breaking wave conditions, it is shown that celerity does not increase monotonically with increasing dimensionless wave steepness. Numerical comparisons between the two algorithms indicate that the Dalrymple algorithm is more accurate for near-breaking waves and requires less computer programming effort. Neither algorithm appears to be able to predict breaking wave conditions as accurately as the COKELET (1977, Philosophical Transactions of the Royal Society of London,A286, 183 230) algorithm. Numerical comparisons of the Dalrymple free surface error convergence criteria with the Chaplin significant figures convergence criteria indicate that the free surface error convergence criterion is more consistent for stream function representations.

Huang, Min-Chih; Hudspeth, Robert T.

46

Designing electron wave functions in assembled nanostructures

NASA Astrophysics Data System (ADS)

We use the scanning tunneling microscope to not only to map electron wave functions but also to engineer them. By assembling nanostructures from individual atoms and molecules, we confine two-dimensional electronic states into closed electron resonators, or "quantum corrals". Precise control over the geometry of these structures allows electronic states to be tailored to suit particular experiments. Specifically, we design wave functions that enable studies of normally inaccessible quantum phases. First, we create pairs of quantum corrals with shapes drawn from contemporary mathematics. Exploiting special topological relationships between these structures, we retrieve internal quantum phase of electron wave functions without using interferometry. Second, we demonstrate that adding a single atom to a quantum corral can cause its electronic states to recombine into coherent superpositions. The real-space position of the additional atom controls abstract superposition phase angles, enabling arbitrary time-independent superpositions to be created. Third, we study geometric phase by creating a series of quantum corrals that traverse a closed path through a parameter space. Tracking the corral wave functions reveals a phase shift depending solely on the path taken, directly visualizing Berry's phase evolution in a quantum system. Finally, we extend beyond closed electron resonators and engineer wave functions in open nanostructures. We show that arbitrary patterns can be encoded into electronic states, creating a new form of holography on the nanoscale. We exhibit letters written in electron density rather than with atomic matter, and show that multiple letters may be simultaneously embedded at different energies in the same region of space. Because the wavelength of the electrons diminishes as energy is increased, this technique allows local information densities that exceed the conventionally assumed limit of 1 bit per atom. Taken together, the results in this thesis demonstrate unprecedented control of electron states in condensed matter and illuminate fundamental quantum phases that underlie systems ranging from coherent electronic devices to complex quantum materials.

Moon, Christopher Ryan

47

Impact detection using ultrasonic waves based on artificial immune system

NASA Astrophysics Data System (ADS)

This paper presents a structural health monitoring system for judging structural condition of metallic plates by analyzing ultrasonic waves. Many critical accidents of structures like buildings and aircrafts are caused by small structural errors; cracks and loosened bolts etc. This is a reason why we need to detect little errors at an early stage. Moreover, to improve precision and to reduce cost for damage detection, it is necessary to build and update the database corresponding to environmental change. This study focuses our attention on the automatable structures, specifically, applying artificial immune system (AIS) algorithm to determine the structure safe or not. The AIS is a novelty computational detection algorithm inspired from biological defense system, which discriminates between self and non-self to reject nonself cells. Here, self is defined to be normal data patterns and non-self is abnormal data patterns. Furthermore, it is not only pattern recognition but also it has a storage function. In this study, a number of impact resistance experiments of duralumin plates, with normal structural condition and abnormal structural condition, are examined and ultrasonic waves are acquired by AE sensors on the surface of the aluminum plates. By accumulating several feature vectors of ultrasonic waves, a judging method, which can determine an abnormal wave as nonself, inspired from immune system is created. The results of the experiments show good performance of this method.

Okamoto, Keisuke; Mita, Akira

2009-03-01

48

Localized Single-Photon Wave Functions in Free Space

We solve the joint open problems of photon localization and single-photon wave functions in the context of spontaneous emission from an excited atom in free space. Our wave functions are well-defined members of a discrete orthonormal function set. Both the degree and shape of the localization are controlled by entanglement mapping onto the atom wave function, even though the atom

K. W. Chan; C. K. Law; J. H. Eberly

2002-01-01

49

Molecular Wave Functions and Inelastic Atomic Collisions

A theoretical interpretation is given of inelastic atomic collisions, especially violent cases where the atomic electron shells deeply interpenetrate. The basis set consists of a product of single-particle, hydrogen-molecular-ion orbital wave functions. The occurrence of large energy losses at critical internuclear distances can be seen as a result of the promotion of inner-shell electrons predicted by molecular-orbital (MO) theory. Energy

William Lichten

1967-01-01

50

How fast is the wave function collapse?

NASA Astrophysics Data System (ADS)

Using complex quantum Hamilton-Jacobi formulation, a new kind of non-linear equations is proposed that have almost classical structure and extend the Schrödinger equation to describe the collapse of the wave function as a finite-time process. Experimental bounds on the collapse time are of order 0.1 ms to 0.1 ps and the areas where sensitive probes of the possible collapse dynamics can be done include Bose-Einstein condensates, ultracold neutrons or ultrafast optics.

Ignatiev, A. Yu

2013-02-01

51

Photon wave functions and quantum interference experiments

We present a general theory to describe two-photon interference, including a formal description of few photon intereference in terms of single-photon amplitudes. With this formalism, it is possible to describe both frequency entangled and separable two-photon interference in terms of single-photon wave functions. Using this description, we address issues related to the physical interpretation of two-photon interference experiments. We include

G. G. Lapaire; J. E. Sipe

2006-01-01

52

Wave function methods for fractional electrons

NASA Astrophysics Data System (ADS)

Determining accurate chemical potentials is of considerable interest in various chemical and physical contexts: from small molecular charge-transfer complexes to bandgap in bulk materials such as semi-conductors. Chemical potentials are typically evaluated either by density functional theory, or, alternatively, by computationally more intensive Greens function based GW computations. To calculate chemical potentials, the ground state energy needs to be defined for fractional charges. We thus explore an extension of wave function theories to fractional charges, and investigate the ionization potential and electron affinity as the derivatives of the energy with respect to the electron number. The ultimate aim is to access the chemical potential of correlated wave function methods without the need of explicitly changing the numbers of electrons, making the approach readily applicable to bulk materials. We find that even though second order perturbation theory reduces the fractional charge error considerably compared to Hartree-Fock and standard density functionals, higher order perturbation theory is more accurate and coupled-cluster approaches are even more robust, provided the electrons are bound at the Hartree-Fock level. The success of post-HF approaches to improve over HF relies on two equally important aspects: the integer values are more accurate and the Coulomb correlation between the fractionally occupied orbital and all others improves the straight line behavior significantly as identified by a correction to Hartree-Fock. Our description of fractional electrons is also applicable to fractional spins, illustrating the ability of coupled-cluster singles and doubles to deal with two degenerate fractionally occupied orbitals, but its inadequacy for three and more fractional spins, which occur, for instance, for spherical atoms and when dissociating double bonds. Our approach explores the realm of typical wave function methods that are applied mostly in molecular chemistry, but become available to the solid state community and offer the advantage of an integrated approach: fundamental gap, relative energies, and optimal geometries can be obtained at the same level.

Steinmann, Stephan N.; Yang, Weitao

2013-08-01

53

Calculation of Morse Wave Functions with Programmable Deskton Calculators.

National Technical Information Service (NTIS)

It is very helpful for the student of electronic transitions in diatomic molecules to be able to visualize vibrational wave functions, probability distributions and the overlap of wave functions. As the result of recent advances in programmable calculator...

G. D. Brabson

1973-01-01

54

Impact of shear and curvature on surface gravity wave stress

NASA Astrophysics Data System (ADS)

It has been shown that surface gravity wave stress is sensitive to the low level wind profile shape. The simplest way of incorporating those effects in a theoretical model has been recently proposed, using a second order WKB approach, which leads to closed analytical formulae for the surface stress as a function of stability, low level wind and its two first derivatives (shear and curvature). In the present study, we assess the impact of those calculations on global scale gravity wave stress and the corresponding torque, using 6-hourly data from ERA-40 reanalysis, at full resolution. While the theory shows that linear wind shear leads to a reduced stress and curvature may lead to stress enhancement, the present results indicate that the latter effect is dominant. However, when one looks for regionally integrated stress fields for the large mountain ranges, where cancellation effects take place thorough time and space integration, the overall effect is one of drag enhancement in regions of dominant easterly flow, namely Antarctica and East Africa, leading to a slight reduction of the global westerly torque due to mountain waves. Drag enhancement due to wind profile curvature seems to be an important effect in Antarctic flow, where it accounts for a 50% increase in the mean regional torque, with implied consequences for the dynamics of the polar vortex.

Miranda, P. M. A.; Martins, J. P. A.; Teixeira, M. A. C.

2009-09-01

55

Electron Wave Function in Armchair Graphene Nanoribbons

NASA Astrophysics Data System (ADS)

By using analytical solution of a tight-binding model for armchair nanoribbons, it is confirmed that the solution represents the standing wave formed by intervalley scattering and that pseudospin is invariant under the scattering. The phase space of armchair nanoribbon which includes a single Dirac point is specified. By examining the effects of boundary perturbations on the wave function, we suggest that the existance of a strong boundary potential is inconsistent with the observation in a recent scanning tunneling microscopy. Some of the possible electron-density superstructure patterns near a step armchair edge located on top of graphite are presented. It is demonstrated that a selection rule for the G band in Raman spectroscopy at graphene edge can be most easily reproduced with the analytical solution.

Sasaki, Ken-ichi; Wakabayashi, Katsunori; Enoki, Toshiaki

2011-04-01

56

A Hammer-Impact, Aluminum, Shear-Wave Seismic Source

Near-surface seismic surveys often employ hammer impacts to create seismic energy. Shear-wave surveys using horizontally polarized waves require horizontal hammer impacts against a rigid object (the source) that is coupled to the ground surface. I have designed, built, and tested a source made out of aluminum and equipped with spikes to improve coupling. The source is effective in a variety of settings, and it is relatively simple and inexpensive to build.

Haines, Seth S.

2007-01-01

57

Position Search Technique for Unknown Wave Sources Using Spherical Wave Function

Estimation of wave source position is important technique for searching unknown noise source in electromagnetic compatibility measurement. In this article, a new position search technique for unknown wave sources is proposed by using the spherical vector wave function and point-matching method. In this technique, a few virtual boundaries are placed on surrounding areas, which includes the unknown wave sources. In

Kuniyuki Motojima; Hiroyuki Sutou

2011-01-01

58

Wave functions of log-periodic oscillators

We use the Lewis and Riesenfeld invariant method [J. Math. Phys. 10, 1458 (1969)] and a unitary transformation to obtain the exact Schroedinger wave functions for time-dependent harmonic oscillators exhibiting log-periodic-type behavior. For each oscillator we calculate the quantum fluctuations in the coordinate and momentum as well as the quantum correlations between the coordinate and momentum. We observe that the oscillator with m=m{sub 0}t/t{sub 0} and {omega}={omega}{sub 0}t{sub 0}/t, which exhibits an exact log-periodic oscillation, behaves as the harmonic oscillator with m and {omega} constant.

Bessa, V.; Guedes, I. [Departamento de Fisica, Universidade Federal do Ceara, Campus do Pici, Fortaleza, CE 60455-760 (Brazil)

2011-06-15

59

Comparison of wave structure functions for intensity profiles

NASA Astrophysics Data System (ADS)

We give a list of available wave structure functions (WSFs) of a spherical wave, simultaneously providing some derivation details. The aim is to assess the impact of these WSFs on intensity profiles of various beams propagating in turbulence. For comparisons, coherent and partially coherent fundamental Gaussian, hyperbolic, sinusoidal and annular Gaussian beams are chosen. Comparisons are made by calculating the difference between the intensity profiles of the analytic solution that uses the normalized WSF with quadratic approximation and the intensity profiles obtained by numerically solving the quadruple extended Huygens-Fresnel integral containing other WSFs. The graphical results show that in general the differences arising from the use of different WSFs are not substantial. Such differences become much greater however toward the complete incoherence limit and at relatively higher structure constant values. Even then, at these extremes, the receiver intensity levels are much reduced, making such big differences immaterial.

Eyyubo?lu, H. T.

2009-03-01

60

Wave and Fracture Phenomena in Impacted Ceramics.

National Technical Information Service (NTIS)

An optical measuring technique in combination with high speed photography is provided to solve the problem of this contract, the investigation of wave and fracture phenomena in opaque ceramic materials. Surface disturbances caused by these mechanical even...

S. Winkler

1988-01-01

61

Towards an Accurate Wave Function for Positronium Hydride

A variational wave function for the ground state of positronium hydride is presented. The wave function is considerably more accurate than any previously reported. The only simplifications used are (a) only kinetic and Coulombic potential energy terms are included in the Hamiltonian, (b) the motion of the proton is ignored, and (c) the nucleus-positron distance is excluded from the wave

C. F. Lebeda; David M. Schrader

1969-01-01

62

Variational wave functions for homogenous Bose systems

We study variational wave functions of the product form, factorizing according to the wave vectors k, for the ground state of a system of bosons interacting via positive pair interactions with a positive Fourier transform. Our trial functions are members of different orthonormal bases in Fock space. Each basis contains a quasiparticle vacuum state and states with an arbitrary finite number of quasiparticles. One of the bases is that of Valatin and Butler (VB), introduced fifty years ago and parametrized by an infinite set of variables determining Bogoliubov's canonical transformation for each k. In another case, inspired by Nozieres and Saint James the canonical transformation for k=0 is replaced by a shift in the creation/annihilation operators. For the VB basis we prove that the lowest energy is obtained in a state with {approx}{radical}(volume) quasiparticles in the zero mode. The number of k=0 physical particles is of the order of the volume and its fluctuation is anomalously large, resulting in an excess energy. The same fluctuation is normal in the second type of optimized bases, the minimum energy is smaller and is attained in a vacuum state. Associated quasiparticle theories and questions about the gap in their spectrum are also discussed.

Sueto, Andras [Research Institute for Solid State Physics and Optics, Hungarian Academy of Sciences, P. O. Box 49, H-1525 Budapest (Hungary); Szepfalusy, Peter [Research Institute for Solid State Physics and Optics, Hungarian Academy of Sciences, P. O. Box 49, H-1525 Budapest (Hungary); Department of Physics of Complex Systems, Eoetvoes University, H-1117 Budapest (Hungary)

2008-02-15

63

Impact of simulated heat waves on soybean physiology and yield

Technology Transfer Automated Retrieval System (TEKTRAN)

With increases in mean global temperatures and associated climate change, extreme temperature events are predicted to increase in both intensity and frequency. Despite the clearly documented negative public health impacts of heat waves, the impact on physiology and yields of key agricultural species...

64

Completeness of the Coulomb scattering wave functions

NASA Astrophysics Data System (ADS)

The completeness of the eigenfunctions of a self-adjoint Hamiltonian, which is the basic ingredient of quantum mechanics, plays an important role in nuclear reaction and nuclear-structure theory. Here we present the first formal proof of the completeness of the two-body Coulomb scattering wave functions for a repulsive unscreened Coulomb potential using Newton’s method (R. Newton, J. Math. Phys. 1, 319 (1960)). The proof allows us to claim that the eigenfunctions of the two-body Hamiltonian, with the potential given by the sum of the repulsive Coulomb plus short-range (nuclear) potentials, form a complete set. It also allows one to extend Berggren’s approach for the modification of the complete set of eigenfunctions by including the resonances for charged particles. We also demonstrate that the resonant Gamow functions with Coulomb tail can be regularized using Zel’dovich’s regularization method.

Mukhamedzhanov, A. M.; Akin, M.

2008-07-01

65

New summation rules for coulomb wave functions

Sums of products of the Coulomb wave functions over degenerate manifolds have been obtained in a closed form. These sums appear in many atomic and molecular problems. The sums have been obtained making use of the properties of the Coulomb Green's function G(r, r('),E), in the limit E-->E(n), where E(n) is the eigenenergy of the hydrogenlike atomic ion. The closed Hostler-Pratt form of G in the coordinate representation has been used. The sums calculated are a consequence of the n degeneracy of the Coulomb atomic energy levels. This itself, as is well known, follows from the four-dimensional symmetry of the Coulomb problem for the hydrogen atom. PMID:11015936

Chibisov; Ermolaev; Brouillard; Cherkani

2000-01-17

66

Second order distorted wave calculations for electron impact ionization processes

NASA Astrophysics Data System (ADS)

Electron impact ionization of atoms provides a fundamental test of the current understanding of atomic structure as well as our understanding of the three body problem. Triple differential cross sections (TDCS), measured in the coincidence experiment, provide the most sensitive test of the theory of electron impact ionization processes. It was found two decades ago that second-order effects were crucial in explaining both the positions and magnitudes of the binary and recoil peaks in the TDCS. However, the existing theoretical calculations of second-order amplitudes typically resort to simplifying approximations, such as the closure approximation or neglecting the real part of the Green's function, to make the calculation tractable. In this work, we have developed a second-order distorted wave (DWB2) theory for atomic ionization which does not make these approximations. The DWB2 theory has been used to calculate the TDCS for electron impact ionization of hydrogen. It is found that the DWB2 results are in good agreement with absolute experimental measurements for incident energy greater than 100 eV. We have also performed DWB2 calculations for electron impact ionization of helium with the residual ion left in the n=1 and 2 states at intermediate energies in coplanar asymmetric geometry. Both the neutral and ionic distorting potentials are employed for the projectile in the final state. It has been found that the DWB2 results with the ionic distorting potential are in better agreement with experiment for the case in which the residual ion is left in the excited states. We have also performed the calculations to check the validity of the closure approximation and the simplified Green's function approximation and found that these approximations are not accurate for non-coplanar geometry and low incident energies.

Chen, Zhangjin

67

Expansion of Continuum Functions on Resonance Wave Functions and Amplitudes. 2.

National Technical Information Service (NTIS)

To overcome difficulties with wave functions of continuum spectrum (for example, in a shell model with continuum) the pole expansion (by the Mittag-Leffler theorem) of wave functions, scattering amplitudes and the Green functions at positive energies are ...

J. Bang F. A. Gareev M. H. Gizzatkulov S. A. Goncharov

1978-01-01

68

Energy partitioning in {sup 1}S-wave electron-impact ionization of atomic hydrogen

Results of calculations of the integrated cross section and the energy distribution for ionization of ground-state hydrogen by {sup 1}S-wave electron impact are presented. The breakup amplitude is expressed as a volume integral that contains an approximate final-state wave function which accounts for postcollision dynamic screening. The error in this wave function is accounted for by the response function, which is represented on a real discrete (Sturmian) basis, with its physical branch specified by the arrow of time. It is found that the energy distribution is primarily convex for impact energies from about 2 to 10 eV above threshold, and primarily flat from about 10 to 20 eV above threshold. The shape of the energy distribution appears to reflect both the competition between escape and recapture, and the substantial postcollision exchange of energy between the electrons. A rough, nonclassical criterion for predicting the curvature of the energy distribution is derived.

Shakeshaft, Robin [Physics Department, University of Southern California, Los Angeles, California 90089-0484 (United States)

2010-03-15

69

String wave function across a Kasner singularity

A collision of orbifold planes in 11 dimensions has been proposed as an explanation of the hot big bang. When the two planes are close to each other, the winding membranes become the lightest modes of the theory, and can be effectively described in terms of fundamental strings in a ten-dimensional background. Near the brane collision, the 11-dimensional metric is a Euclidean space times a 1+1-dimensional Milne universe. However, one may expect small perturbations to lead into a more general Kasner background. In this paper we extend the previous classical analysis of winding membranes to Kasner backgrounds, and using the Hamiltonian equations, solve for the wave function of loops with circular symmetry. The evolution across the singularity is regular, and explained in terms of the excitement of higher oscillation modes. We also show there is finite particle production and unitarity is preserved.

Copeland, Edmund J.; Niz, Gustavo [School of Physics and Astronomy, University of Nottingham, University Park, Nottingham NG7 2RD (United Kingdom); Turok, Neil [Perimeter Institute for Theoretical Physics, 31 Caroline Street N, Waterloo, Ontario N2L2Y5 (Canada)

2010-06-15

70

Improved variational wave functions for simple quantum liquids

We review variational calculations with a Jastrow wave function and show they are inadequate to calculate the zero-temperature equation of state E(rho) for liquid helium. The importance of the Feynman-Cohen backflow around a moving particle is then discussed, and a variational wave function incorporating backflow is proposed. Results with this wave function are discussed for 3He, 4He and the v2

K. E. Schmidt; V. R. Pandharipande

1979-01-01

71

Physical measurements of breaking wave impact on a floating wave energy converter

NASA Astrophysics Data System (ADS)

Marine energy converter must both efficiently extract energy in small to moderate seas and also successfully survive storms and potential collisions. Extreme loads on devices are therefore an important consideration in their design process. X-MED is a SuperGen UKCMER project and is a collaboration between the Universities of Manchester, Edinburgh and Plymouth and the Scottish Association for Marine Sciences. Its objective is to extend the knowledge of extreme loads due to waves, currents, flotsam and mammal impacts. Plymouth Universities contribution to the X-MED project involves measuring the loading and response of a taut moored floating body due to steep and breaking wave impacts, in both long crested and directional sea states. These measurements are then to be reproduced in STAR-CCM+, a commercial volume of fluid CFD solver, so as to develop techniques to predict the wave loading on wave energy converters. The measurements presented here were conducted in Plymouth Universities newly opened COAST laboratories 35m long, 15.5m wide and 3m deep ocean basin. A 0.5m diameter taut moored hemispherical buoy was used to represent a floating wave energy device or support structure. The changes in the buoys 6 degree of freedom motion and mooring loads are presented due to focused breaking wave impacts, with the breaking point of the wave changed relative to the buoy.

Hann, Martyn R.; Greaves, Deborah M.; Raby, Alison

2013-04-01

72

Trial wave functions for high-pressure metallic hydrogen

Many body trial wave functions are the key ingredient for accurate Quantum Monte Carlo estimates of total electronic energies in many electron systems. In the Coupled Electron-Ion Monte Carlo method, the accuracy of the trial function must be conjugated with the efficiency of its evaluation. We report recent progress in trial wave functions for metallic hydrogen implemented in the Coupled

Carlo Pierleoni; Kris T. Delaney; Miguel A. Morales; David M. Ceperley; Markus Holzmann

2008-01-01

73

Semiclassical approach to K shell ionization: hydrogenic wave functions

Proton induced K shell ionization cross sections in several elements were calculated. Semiclassical approximation with momentum space approach, hydrogenic wave functions and outer screening according to the prescription of Bethe was used. Comparison with other semiclassical and Dirac-Hartree-Slater [DHS] plane wave cross sections indicates that this type of screening — largely used in plane wave methods — implies a less

Ž. Šmit

1991-01-01

74

Photon wave functions, wave-packet quantization of light, and coherence theory

The monochromatic Dirac and polychromatic Titulaer Glauber quantized field theories (QFTs) of electromagnetism are derived from a photon-energy wave function in much the same way that one derives QFT for electrons, i.e., by quantization of a single-particle wave function. The photon wave function and its equation of motion are established from the Einstein energy momentum mass relation, assuming a local

Brian J. Smith; M. G. Raymer

2007-01-01

75

Photon wave functions, wave-packet quantization of light, and coherence theory

The monochromatic Dirac and polychromatic Titulaer–Glauber quantized field theories (QFTs) of electromagnetism are derived from a photon-energy wave function in much the same way that one derives QFT for electrons, i.e., by quantization of a single-particle wave function. The photon wave function and its equation of motion are established from the Einstein energy–momentum–mass relation, assuming a local energy density. This

Brian J. Smith; M. G. Raymer

2007-01-01

76

Shock Waves Impacting Composite Material Plates: The Mutual Interaction

NASA Astrophysics Data System (ADS)

High-performance, fiber-reinforced polymer composites have been extensively used in structural applications in the last 30 years because of their light weight combined with high specific stiffness and strength at a rather low cost. The automotive industry has adopted these materials in new designs of lightweight vehicles. The mechanical response and characterization of such materials under transient dynamic loading caused with shock impact induced by blast is not well understood. Air blast is associated with a fast traveling shock front with high pressure across followed by a decrease in pressure behind due to expansion waves. The time scales associated with the shock front are typically 103 faster than those involved in the expansion waves. Impingement of blast waves on structures can cause a reflection of the wave off the surface of the structure followed by a substantial transient aerodynamic load, which can cause significant deformation and damage of the structure. These can alter the overpressure, which is built behind the reflected shock. In addition, a complex aeroelastic interaction between the blast wave and the structure develops that can induce reverberation within an enclosure, which can cause substantial overpressure through multiple reflections of the wave. Numerical simulations of such interactions are quite challenging. They usually require coupled solvers for the flow and the structure. The present contribution provides a physics-based analysis of the phenomena involved, a critical review of existing computational techniques together with some recent results involving face-on impact of shock waves on thin composite plates.

Andreopoulos, Yiannis

2013-02-01

77

Hadronic wave function in quantum chromodynamics

The underlying link between hadronic phenomena in quantum chromodynamics at large and small distance is the hadronic wavefunction. The theoretical and empirical constraints on the hadronic wave-function and hadronic structure functions; the predictions of perturbative QCD for the large transverse momentum tail of the Fock state infinite momentum wavefunction psi (k/sub perpendicular to i/,x/sub i/,s/sub i/); the valence Fock state meson wavefunctions from the meson decay; the evolution equations of the distribution amplitudes; and a simplified model for the basic wavefunctions are presented. In particular, a new type of low energy theorem is obtained for the pion wavefunction from the ..pi../sup 0/ ..-->.. ..gamma gamma... This result, together with the constraint on the valence wavefunction from the ..pi../sup 0/ ..-->.. ..mu nu.. decay, leads to the probability of finding the valence vertical bar q anti q > state. All these constraints allow construction of a possible model which describes hadronic wavefunctions, probability amplitudes, and distributions. Results are compared with data for form factors and the deep inelastic processes. This work represents a first attempt to construct a model of hadronic structure which is consistent with data and QCD at large and small distances.

Brodsky, S.J.; Huang, T.; Lepage, G.P.

1980-01-01

78

The effects of shock wave and quasi-traveling wave in the mechanical impact test

It is well-known that the numerical value is always larger than the measured value, amounting to many times, if we calculate\\u000a the stress of the specimen in the impulse test using the NASTRAN and ANSYS (N-A) software. We believe that the impact induces\\u000a shock wave or quasi-traveling wave in the specimen, which can qualitatively explain the discrepancy of the two

Mei Wu; ZhongFeng Sun; LuMei Zhang; Yong Chen; LinHong Ji

2010-01-01

79

Stress wave induced damage and fracture in impacted glasses

The conditions for crack nucleation under impact loading were investigated system- atically for four glasses which differ in their chemical composition, hardness and material den- sity. Edge-on impact experiments were carried out with blunt steel cylinders within the velocity range from 20 m\\/s to 1000 m\\/s. The propagation of shock waves, of primary and secondary cracks and crack systems and

H. Senf; E. Strassburger; H. Rothenhausler

1994-01-01

80

Pressure-shear stress wave analysis in plate impact experiments

Numerical results are presented for the combined longitudinal and shear wave propagation in an elastic-viscoplastic solid as it occurs in high strain-rate plate impact experiments. Special attention is paid to the initial stage of the impact experiment and the effects of the specimen thickness, elastic impedances of flyer-anvil plates, and viscoplastic properties of materials on the time to reach a

Wei Tong

1997-01-01

81

Impact of Fog on Electromagnetic Wave Propagation

This experiment was designed to explore the impact of fog on electromagnetic radiation, in particular microwaves and infrared light. For years law enforcement agencies have used microwave radiation (radar guns) to measure the speed of vehicles, and the last ten years has seen increased use of LIDAR, which uses 905-nm infrared radiation rather than microwaves. To evaulate the effect of

Jonathon Morris; Daniel Fleisch

2002-01-01

82

Six Impossible Things: Fractional Charge From Laughlin's Wave Function

The Laughlin's wave function is found to be the zero-energy ground state of a {delta}-function Hamiltonian. The finite negative value of the ground state energy which is 91 per cent of Wigner value, can be obtained only when Coulomb correlations are introduced. The Laughlin's wave function is of short range and it overlaps with that of the exact wave functions of small (number of electrons 2 or 5) systems. (i) It is impossible to obtain fractional charge from Laughlin's wave function. (ii) It is impossible to prove that the Laughlin's wave function gives the ground state of the Coulomb Hamiltonian. (iii) It is impossible to have particle-hole symmetry in the Laughlin's wave function. (iv) It is impossible to derive the value of m in the Laughlin's wave function. The value of m in {psi}{sub m} can not be proved to be 3 or 5. (v) It is impossible to prove that the Laughlin's state is incompressible because the compressible states are also likely. (vi) It is impossible for the Laughlin's wave function to have spin. This effort is directed to explain the experimental data of quantum Hall effect in GaAs/AlGaAs.

Shrivastava, Keshav N. [Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur 50603 (Malaysia)

2010-12-23

83

Antipodal focusing of seismic waves after larger meteorite impacts

NASA Astrophysics Data System (ADS)

We examine focusing of seismic waves at the antipode of large terrestrial meteorite impacts, using the Chicxulub impact as our case study. Numerical simulations are based on a spectral-element method, representing the impact as a Gaussian force in time and space. Simulating the impact as a point source at the surface of a spherically symmetric Earth model results in deceptively large peak displacements at the antipode. Earth's ellipticity, lateral heterogeneity and a spatially distributed source limit high-frequency waves from constructively interfering at the antipode, thereby reducing peak displacement by a factor of four. Nevertheless, for plausible impact parameters, we observe peak antipodal displacements of ˜ 4~m, dynamic stresses in excess of 15~bar, and strains of 2 ± 10-5 . While these values are significantly lower than prior estimates, mainly based on a point source in a spherically symmetric Earth model, wave interference en route to the antipode induces ``channels'' of peak stress that are 5~times greater than in surrounding areas. Underneath the antipode we observed ``chimneys'' of peak stress, strain and velocity, with peak values exceeding 50~bar, 10-5 and 0.1~m/s, respectively. Our results put quantitative constraints on the feasibility of impact-induced antipodal volcanism and seismicity, as well as mantle plume and hotspot formation.

Meschede, M.

2011-12-01

84

Exclusive processes of charmonium production and charmonium wave functions

Results obtained by studying the properties of the leading-twist wave functions for the S- and P-wave states of charmonia are presented. Wave-function models that can be used to calculate various processes involving the production of these mesons were constructed on the basis of these investigations. Calculations for some exclusive processes of charmonium production were performed within the models in question.

Braguta, V. V., E-mail: braguta@mail.ru; Likhoded, A. K., E-mail: Anatolii.Likhoded@ihep.ru; Luchinsky, A. V., E-mail: Alexey.Luchinsky@ihep.ru [Institute for High Energy Physics (Russian Federation)

2012-01-15

85

Retarded Green's function of a Vainshtein system and Galileon waves

NASA Astrophysics Data System (ADS)

Motivated by the desire to test modified gravity theories exhibiting the Vainshtein mechanism, we solve in various physically relevant limits, the retarded Galileon Green’s function (for the cubic theory) about a background sourced by a massive spherically symmetric static body. The static limit of our result will aid us, in a forthcoming paper, in understanding the impact of Galileon fields on the problem of motion in the solar system. In this paper, we employ this retarded Green’s function to investigate the emission of Galileon radiation generated by the motion of matter lying deep within the Vainshtein radius rv of the central object: acoustic waves vibrating on its surface, and the motion of compact bodies gravitationally bound to it. If ? is the typical wavelength of the emitted radiation, and r0 is the typical distance of the source from the central mass, with r0?rv, then, compared to its noninteracting massless scalar counterpart, we find that the Galileon radiation rate is suppressed by the ratio (rv/?)-3/2 at the monopole and dipole orders at high frequencies rv/??1. However, at high enough multipole order, the radiation rate is enhanced by powers of rv/r0. At low frequencies rv/??1, and when the motion is nonrelativistic, Galileon waves yield a comparable rate for the monopole and dipole terms, and are amplified by powers of the ratio rv/r0 for the higher multipoles.

Chu, Yi-Zen; Trodden, Mark

2013-01-01

86

Evidence for shock wave effect of meteoritic impact

NASA Astrophysics Data System (ADS)

There is material evidence for the existence of shock waves generated by meteoritic impact, as demonstrated by the pressure and temperature dependent formation processes that exist in the memory of constituent minerals. Stishovite of high-pressure type silica mineral can be observed to be a relict of the compression stage of shock impact. Almost all of the silica minerals evolved from shock impact phenomena are alpha-quartz crystals of a low-temperature type silica polymorph. By using precise measurements of cell parameters and the corresponding calculated density of the quartz crystal grains collected by an ultrasonic cutter method, shocked quartz grains can be interpreted as the principal relict of meteoritic impact from natural impact craters, artificial impact craters and Cretaceous-Tertiary boundary samples.

Miura, Y.

1991-03-01

87

Binding Energy Calculations Using the Molecular Orbital Wave Function.

National Technical Information Service (NTIS)

The molecular orbital wave function is used in describing the 4 N-nuclei internal wave function. Using the variational technique the binding energies of the nuclei exp 12 C, exp 16 O, exp 20 Ne and exp 24 Mg are calculated using different Skyrm interactio...

M. Y. M. Hassan A. Rabie E. H. Ismail

1982-01-01

88

Natural orbital analysis of nonadiabatic Hâ\\/sup +\\/ wave functions

Previously determined nonadiabatic wave functions for Hâ\\/sup +\\/ (containing several hundred terms) are analyzed by using natural orbitals. This is the first time that the natural orbital concept has been applied to other than purely electronic wave functions. We find that the natural orbital expansion converges rapidly and that five or six terms are sufficient to reproduce the exact expectation

David M. Bishop; Lap M. Cheung

1979-01-01

89

Non-Sequential Behavior of the Wave Function

An experiment is presented in which the alleged progression of a photon's wave function is ``measured'' by a row of superposed atoms. The photon's wave function affects only one out of the atoms, regardless of its position within the row, thereby manifesting not only non-local but also non-sequential characteristics. It also turns out that, out of n atoms, each one

Shahar Dolev; Avshalom C. Elitzur

2001-01-01

90

Imaging a Molecular Orbital Wave Function Using High Harmonic Emission

Single-electron molecular orbital wave functions are mathematical constructs that are used to describe the multi-electron wave function of molecules. The highest lying orbitals are of particular interest since they are responsible for the chemical properties of molecules. To observe them change as molecular bonds are formed and broken is to observe the essence of chemistry. Yet single orbitals are difficult

David Villeneuve

2005-01-01

91

The small K ? component in the K* wave functions

NASA Astrophysics Data System (ADS)

We use a recently developed formalism which generalizes Weinberg's compositeness condition to partial waves higher than s -wave in order to determine the probability of having a K ? component in the K* wave function. A fit is made to the K ? phase shifts in p -wave, from where the coupling of K* to K ? and the K ? loop function are determined. These ingredients allow us to determine that the K* is a genuine state, different from a K ? component, in a proportion of about 80%.

Xiao, C. W.; Aceti, F.; Bayar, M.

2013-02-01

92

Electronic wave functions of quasiperiodic systems in momentum space

NASA Astrophysics Data System (ADS)

In quasicrystalline tilings often multifractal electronic wave functions can be found. In order to obtain a better insight into their localization properties, we study the wave functions of quasiperiodic tilings in momentum space. The models are based on one-dimensional quasiperiodic chains, in which the atoms are coupled by weak and strong bonds aligned according to the metallic-mean sequences. The associated hypercubic tilings and labyrinth tilings in d dimensions are then constructed from the direct product of d such chains. The results show that each wave function is described by a hierarchy of wave vectors and is always dominated by a single wave vector which is directly related to the energy eigenvalue of the wave function. The corresponding spectral function of the systems shows a hierarchy of branches with different intensities. Each branch is a copy of the main branch containing the dominant wave vectors for each wave function. Using perturbation theory and a renormalization group approach, we determine the shape of the branches for the limit of weak and strong coupling.

Rolof, Sebastian; Thiem, Stefanie; Schreiber, Michael

2013-09-01

93

Impact of insomnia on future functioning of adolescents

Objective: To examine the impact of insomnia among adolescents on somatic, interpersonal, and psychological functioning using data from a two-wave, prospective study. Methods: Subjects were adolescents 11–17 years of age sampled from managed care enrollment rosters in the United States. The baseline sample was 4175 and the follow-up sample a year later was 3136. Data were collected using computer-assisted personal

Robert E Roberts; Catherine Ramsay Roberts; Irene Ger Chen

2002-01-01

94

Sech wave packets, their Wigner functions and Bohmian trajectories

NASA Astrophysics Data System (ADS)

The free particle non-relativistic Schrödinger evolution of a sech wave packet, and the corresponding Wigner function and Bohmian trajectories, are studied. The overall translation and dispersion dynamics are qualitatively similar to corresponding Gaussian wave packets, as is to be expected. On the other hand, certain bizarre and completely unexpected features are also observed, such as wave packet pinching and the instantaneous formation of infinitely many nodes, despite the apparent lack of an interference source.

Schiff, Jeremy; Poirier, Bill

2012-10-01

95

Optimized Perturbation Theory for Wave Functions of Quantum Systems

The notion of the optimized perturbation, which has been successfully applied to energy eigenvalues, is generalized to treat wave functions of quantum systems. The key ingredient is to construct an envelope of a set of perturbative wave functions. This leads to a condition similar to that obtained from the principle of minimal sensitivity. Applications of the method to the quantum anharmonic oscillator and the double well potential show that uniformly valid wave functions with correct asymptotic behavior are obtained in the first-order optimized perturbation even for strong couplings. {copyright} {ital 1997} {ital The American Physical Society}

Hatsuda, T.; Tanaka, T. [Institute of Physics, University of Tsukuba, Tsukuba, Ibaraki 305 (Japan); Kunihiro, T. [Faculty of Science and Technology, Ryukoku University, Seta, Ohtsu, 520-21 (Japan)

1997-04-01

96

Proton Wave Functions in a Uniform Magnetic Field

The wave function of the d-quark in the ground state of the proton, and how it is affected in the presence of a uniform background magnetic field is calculated in lattice QCD. We focus on the wave functions in the Landau and Coulomb gauges. When the quarks are annihilated at different lattice sites, we observe the formation of a scalar u-d diquark pair within the proton in the Landau gauge, which is not present in the Coulomb gauge. The overall distortion of the wave function under a very large magnetic field, as demanded by the quantisation conditions on the field, is quite small.

Roberts, Dale S.; Kamleh, Waseem; Leinweber, Derek B. [Special Research Centre for the Subatomic Structure of Matter and Department of Physics, University of Adelaide 5005 (Australia); Bowman, Patrick O. [Centre for Theoretical Chemistry and Physics and Institute of Natural Sciences, Massey University (Albany), Private Bag 102904, North Shore City 0745 (New Zealand)

2011-05-24

97

Boundary conditions on internal three-body wave functions

For a three-body system, a quantum wave function {Psi}{sub m}{sup {ell}} with definite {ell} and m quantum numbers may be expressed in terms of an internal wave function {chi}{sub k}{sup {ell}} which is a function of three internal coordinates. This article provides necessary and sufficient constraints on {chi}{sub k}{sup {ell}} to ensure that the external wave function {Psi}{sub k}{sup {ell}} is analytic. These constraints effectively amount to boundary conditions on {chi}{sub k}{sup {ell}} and its derivatives at the boundary of the internal space. Such conditions find similarities in the (planar) two-body problem where the wave function (to lowest order) has the form r{sup |m|} at the origin. We expect the boundary conditions to prove useful for constructing singularity free three-body basis sets for the case of nonvanishing angular momentum.

Mitchell, Kevin A.; Littlejohn, Robert G.

1999-10-01

98

Nonstandard jump functions for radically symmetric shock waves

Nonstandard analysis is applied to derive generalized jump functions for radially symmetric, one-dimensional, magnetogasdynamic shock waves. It is assumed that the shock wave jumps occur on infinitesimal intervals and the jump functions for the physical parameters occur smoothly across these intervals. Locally integrable predistributions of the Heaviside function are used to model the flow variables across a shock wave. The equations of motion expressed in nonconservative form are then applied to derive unambiguous relationships between the jump functions for the physical parameters for two families of self-similar flows. It is shown that the microstructures for these families of radially symmetric, magnetogasdynamic shock waves coincide in a nonstandard sense for a specified density jump function.

Baty, Roy S [Los Alamos National Laboratory; Tucker, Don H [UNIV OF UTAH; Stanescu, Dan [UNIV OF WYOMING

2008-01-01

99

Nonstandard jump functions for radially symmetric shock waves

Nonstandard analysis is applied to derive generalized jump functions for radially symmetric, one-dimensional, magnetogasdynamic shock waves. It is assumed that the shock wave jumps occur on infinitesimal intervals, and the jump functions for the physical parameters occur smoothly across these intervals. Locally integrable predistributions of the Heaviside function are used to model the flow variables across a shock wave. The equations of motion expressed in nonconservative form are then applied to derive unambiguous relationships between the jump functions for the physical parameters for two families of self-similar flows. It is shown that the microstructures for these families of radially symmetric, magnetogasdynamic shock waves coincide in a nonstandard sense for a specified density jump function

Baty, Roy S.; Tucker, Don H.; Stanescu, Dan

2008-10-01

100

Probing [alpha]-particle wave functions using ([ital [rvec d

Wave functions of the [alpha] particle corresponding to different [ital S]- and [ital D]-state deuteron-deuteron overlaps, [l angle][ital dd][vert bar][alpha][r angle], were investigated using exact finite-range distorted-wave Born-approximation (DWBA) analyses of ([ital [rvec d

E. R. Crosson; S. K. Lemieux; E. J. Ludwig; W. J. Thompson; M. Bisenberger; R. Hertenberger; D. Hofer; H. Kader; P. Schiemenz; G. Graw; A. M. Eiro; F. D. Santos

1993-01-01

101

Simulations of Wave Propagation in the Jovian Atmosphere after SL9 Impact Events

NASA Astrophysics Data System (ADS)

Our previous numerical investigations into Jovian impacts, including the Shoemaker Levy- 9 (SL9) event (Korycansky et al. 2006 ApJ 646. 642; Palotai et al. 2011 ApJ 731. 3), the 2009 bolide (Pond et al. 2012 ApJ 745. 113), and the ephemeral flashes caused by smaller impactors in 2010 and 2012 (Hueso et al. 2013; Submitted to A&A), have covered only up to approximately 3 to 30 seconds after impact. Here, we present further SL9 impacts extending to minutes after collision with Jupiter’s atmosphere, with a focus on the propagation of shock waves generated as a result of the impact events. Using a similar yet more efficient remapping method than previously presented (Pond et al. 2012; DPS 2012), we move our simulation results onto a larger computational grid, conserving quantities with minimal error. The Jovian atmosphere is extended as needed to accommodate the evolution of the features of the impact event. We restart the simulation, allowing the impact event to continue to progress to greater spatial extents and for longer times, but at lower resolutions. This remap-restart process can be implemented multiple times to achieve the spatial and temporal scales needed to investigate the observable effects of waves generated by the deposition of energy and momentum into the Jovian atmosphere by an SL9-like impactor. As before, we use the three-dimensional, parallel hydrodynamics code ZEUS-MP 2 (Hayes et al. 2006 ApJ.SS. 165. 188) to conduct our simulations. Wave characteristics are tracked throughout these simulations. Of particular interest are the wave speeds and wave positions in the atmosphere as a function of time. These properties are compared to the characteristics of the HST rings to see if shock wave behavior within one hour of impact is consistent with waves observed at one hour post-impact and beyond (Hammel et al. 1995 Science 267. 1288). This research was supported by National Science Foundation Grant AST-1109729 and NASA Planetary Atmospheres Program Grant NNX11AD87G.

Pond, Jarrad W.; Palotai, C.; Korycansky, D.; Harrington, J.

2013-10-01

102

Pediatric Kidney: Functional Outcome After Extracorporeal Shock Wave Lithotripsy

PurposeWe studied the efficacy, functional outcome and morphological changes following extracorporeal shock wave lithotripsy (ESWL*) of renal calculi in a pediatric population.*Dornier Medical Systems, Inc., Marietta, Georgia.

Mahesh C. Goel; Narender S. Baserge; R. V. Ramesh Babu; Sanjay Sinha; Rakesh Kapoor

1996-01-01

103

The photon transverse wave function and its measurement

We report on a technique to measure the photon transverse wave function in coordinate space using a photon-counting, parity-inverting Sagnac interferometer. We present measurements of a TEM10 Hermite-Gaussian beam

B. J. Smith; M. G. Raymer; Bryan Killett; K. Banaszek; I. A. Walmsley

2004-01-01

104

Yang-Mills wave functional in Coulomb gauge

We investigate the dependence of the Yang-Mills wave functional in Coulomb gauge on the Faddeev-Popov determinant. We use a Gaussian wave functional multiplied by an arbitrary power of the Faddeev-Popov determinant. We show, that within the resummation of one-loop diagrams the stationary vacuum energy is independent of the power of the Faddeev-Popov determinant and, furthermore, the wave functional becomes field independent in the infrared, describing a stochastic vacuum. Our investigations show, that the infrared limit is rather robust against details of the variational Ansatz for the Yang-Mills wave functional. The infrared limit is exclusively determined by the divergence of the Faddeev-Popov determinant at the Gribov horizon.

Reinhardt, H.; Feuchter, C. [Institut fuer Theoretische Physik, Auf der Morgenstelle 14, D-72076 Tuebingen (Germany)

2005-05-15

105

Third-Order Coulomb Wave Function and Single Quantum Annihilation

An expression for the third-order Coulomb wave function, correct to order (alphaZ)3 for all momenta and energies, is derived. Using this wave function the total cross section for single-photon emission resulting from a positron annihilating with a K-shell electron (single quantum annihilation), valid to relative order (alphaZ)2, is calculated numerically. The results for lead are compared to the exact answer

C. O. Carroll; R. F. O'Connell

1963-01-01

106

Measurement of light-cone wave functions by diffractive dissociation

Diffractive dissociation of particles can be used to study their light-cone wave function. Results from Fermilab experiment E791 for diffractive dissociation of 500 GeV\\/c?? mesons into di-jets are presented. The results show that the |qq?? light-cone asymptotic wave function describes the data well for Q2 ? 10 (GeV\\/c)2 or more. Evidence for color transparency comes from a measurement of the

Daniel Ashery; Beverly Sackler

2000-01-01

107

B meson wave function from the B>gammalnu decay

We show that the leading-power B meson wave function can be extracted reliably from the photon energy spectrum of the B-->gammalnu decay up to O(1\\/m2b) and O(alpha2s) uncertainty, mb being the b quark mass and alphas the strong coupling constant. The O(1\\/mb) corrections from heavy-quark expansion can be absorbed into a redefined leading-power B meson wave function. The two-parton O(1\\/mb)

Yeo-Yie Charng; Hsiang-Nan Li

2005-01-01

108

Wave-function approach to dissipative processes in quantum optics

A novel treatment of dissipation of energy from a ``small'' quantum system to a reservoir is presented. We replace the usual master equation for the small-system density matrix by a wave-function evolution including a stochastic element. This wave-function approach provides new insight and it allows calculations on problems which would otherwise be exceedingly complicated. The approach is applied here to

Jean Dalibard; Yvan Castin; Klaus Mølmer

1992-01-01

109

The Maxwell wave function of the photon

James Clerk Maxwell unknowingly discovered a correct relativistic, quantum\\u000atheory for the light quantum, forty-three years before Einstein postulated the\\u000aphoton's existence. In this theory, the usual Maxwell field is the quantum wave\\u000afunction for a single photon. When the non-operator Maxwell field of a single\\u000aphoton is second quantized, the standard Dirac theory of quantum optics is\\u000aobtained. Recently,

M. G. Raymer; Brian J. Smith

2006-01-01

110

Functional Neuroanatomy of Human Slow Wave Sleep

The distribution of regional cerebral blood flow (rCBF) was estimated during sleep and wakefulness by using H2 15 O positron emission tomography (PET) and statistical parametric mapping. A group analysis on 11 good sleepers (8 with steady slow wave sleep, SWS) showed a significant negative correla- tion between the occurrence of SWS and rCBF in dorsal pons and mesencephalon, thalami,

Pierre Maquet; Christian Degueldre; Guy Delfiore; Joel Aerts; Jean-Marie Peters; Georges Franck

1997-01-01

111

NASA Astrophysics Data System (ADS)

We propose an improved version of the antisymmetrized quasicluster model (AQCM) to describe a smooth transition from the ?-cluster wave function to the jj-coupling shell model wave function and apply it to the ground state of 12C. The cluster-shell transition in 12C is characterized in AQCM by only two parameters: R representing the distance between ? clusters and the center of mass and ? describing the break of ? clusters. The optimal AQCM wave function for the ground state of 12C is an intermediate state between the three-? cluster state and the shell model state with the p3/2 subshell closure configuration. The result is consistent with that of the antisymmetrized molecular dynamics (AMD), and the optimal AQCM wave function quantitatively agrees with the AMD one, although the number of degrees of freedom in AQCM is significantly fewer.

Suhara, Tadahiro; Itagaki, Naoyuki; Cseh, József; P?oszajczak, Marek

2013-05-01

112

Quantum Monte Carlo with coupled-cluster wave functions

NASA Astrophysics Data System (ADS)

We introduce a many-body method that combines two powerful many-body techniques, viz., quantum Monte Carlo and coupled cluster theory. Coupled cluster wave functions are introduced as importance functions in a Monte Carlo method designed for the configuration interaction framework to provide rigorous upper bounds to the ground-state energy. We benchmark our method on the homogeneous electron gas in momentum space. The importance function used is the coupled cluster doubles wave function. We show that the computational resources required in our method scale polynomially with system size. Our energy upper bounds are in very good agreement with previous calculations of similar accuracy, and they can be systematically improved by including higher order excitations in the coupled cluster wave function.

Roggero, Alessandro; Mukherjee, Abhishek; Pederiva, Francesco

2013-09-01

113

Matter Density and Relativistic Models of Wave Function Collapse

NASA Astrophysics Data System (ADS)

Mathematical models for the stochastic evolution of wave functions that combine the unitary evolution according to the Schrödinger equation and the collapse postulate of quantum theory are well understood for non-relativistic quantum mechanics. Recently, there has been progress in making these models relativistic. But even with a fully relativistic law for the wave function evolution, a problem with relativity remains: Different Lorentz frames may yield conflicting values for the matter density at a space-time point. We propose here a relativistic law for the matter density function. According to our proposal, the matter density function at a space-time point x is obtained from the wave function ? on the past light cone of x by setting the i-th particle position in |?|2 equal to x, integrating over the other particle positions, and averaging over i. We show that the predictions that follow from this proposal agree with all known experimental facts.

Bedingham, Daniel; Dürr, Detlef; Ghirardi, GianCarlo; Goldstein, Sheldon; Tumulka, Roderich; Zanghì, Nino

2013-08-01

114

Climate impact response functions for terrestrial ecosystems

We introduce climate impact response functions as a means for summarizing and visualizing the responses of climate-sensitive sectors to changes in fundamental drivers of global climate change. In an inverse application, they allow the translation of thresholds for climate change impacts ('impact guard-rails') into constraints for climate and atmospheric composition parameters ('climate windows'). It thus becomes feasible to specify long-term

Hans-Martin Füssel; Jelle G. van Minnenb

2001-01-01

115

Climate Impact Response Functions for Terrestrial Ecosystems

We introduce climate impact response functions as a means for summarizing and visualizing the responses of climate-sensitive\\u000a sectors to changes in fundamental drivers of global climate change. In an inverse application, they allow the translation\\u000a of thresholds for climate change impacts (‘impact guard-rails’) into constraints for climate and atmospheric composition parameters\\u000a (‘climate windows’). It thus becomes feasible to specify long-term

Hans-Martin Füssel; Jelle G. van Minnen

2001-01-01

116

Wave impact loads: The role of the flip-through

NASA Astrophysics Data System (ADS)

The impact of waves upon a vertical, rigid wall during sloshing is analyzed with specific focus on the modes that lead to the generation of a flip-through [M. J. Cooker and D. H. Peregrine, ``A model for breaking wave impact pressures,'' in Proceedings of the 22nd International Conference on Coastal Engineering (ASCE, Delft, 1990), Vol. 2, pp. 1473-1486]. Experimental data, based on a time-resolved particle image velocimetry technique and on a novel free-surface tracking method [M. Miozzi, ``Particle image velocimetry using feature tracking and Delaunay tessellation,'' in Proceedings of the 12th International Symposium on Applications of Laser Techniques to Fluid Mechanics (2004)], are used to characterize the details of the flip-through dynamics while wave loads are computed by integrating the experimental pressure distributions. Three different flip-through modes are observed and studied in dependence on the amount and modes of air trapping. No air entrapment characterizes a ``mode (a) flip-through,'' engulfment of a single, well-formed air bubble is typical of a ``mode (b)'' event, while the generation of a fine-scale air-water mixing occurs for a ``mode (c)'' event. Upward accelerations of the flip-through jet exceeding 1500 g have been measured and the generation/collapse process of a small air cavity is described in conjunction with the available pressure time histories. Predictions of the vertical pressure distributions made with the pressure-impulse model of Cooker and Peregrine [M. J. Cooker and D. H. Peregrine, ``Pressure-impulse theory for liquid impact problems,'' J. Fluid Mech. 297, 193 (1995)] show good agreement with the experimental data.

Lugni, C.; Brocchini, M.; Faltinsen, O. M.

2006-12-01

117

POINTWISE GREEN FUNCTION BOUNDS AND STABILITY OF COMBUSTION WAVES

Generalizing similar results for viscous shock and relaxation waves, we establish sharp pointwise Green function bounds and linearized and nonlinear stability for traveling wave solutions of an abstract viscous combustion model including both Majda's model and the full reacting compressible Navier-Stokes equations with artificial viscosity with general multi-species reaction and reaction-dependent equation of state, under the necessary condi- tions of

GREGORY LYNG; MOHAMMADREZA ROOFI; BENJAMIN TEXIER; KEVIN ZUMBRUN

2008-01-01

118

Inside looking out: Probing JIMWLK wave functions with BFKL calculations

We investigate the relation between the eigenvalues and eigenfunctions of the Balitsky-Fadin-Kuraev-Lipatov (BFKL) and Jalilian-Marian-Iancu-McLerran-Weigert-Leonidov-Kovner (JIMWLK/KLWMIJ) Hamiltonians. We show that the eigenvalues of the BFKL Hamiltonians are also exact eigenvalues of the KLWMIJ (and JIMWLK) Hamiltonian, albeit corresponding to possibly non-normalizable eigenfunctions. The question whether a given eigenfunction of BFKL corresponds to a normalizable eigenfunction of KLWMIJ is rather complicated, except in some obvious cases, and requires independent investigation. As an example to illustrate this relation we concentrate on the color octet exchange in the framework of KLWMIJ Hamiltonian. We show that it corresponds to the reggeized gluon exchange of BFKL, and find first correction to the BFKL wave function, which has the meaning of the impact factor for shadowing correction to the Reggeized gluon. We also show that the bootstrap condition in the KLWMIJ framework is satisfied automatically and does not carry any additional information to that contained in the second quantized structure of the KLWMIJ Hamiltonian. This is an example of how the bootstrap condition inherent in the t-channel unitarity arises in the s-channel picture.

Altinoluk, Tolga; Kovner, Alex [Physics Department, University of Connecticut, 2152 Hillside Road, Storrs, Connecticut 06269 (United States); Levin, Eugene [Departamento de Fisica, Universidad Tecnica Federico Santa Maria, Avenida Espana 1680, Casilla 110-V, Valparaiso (Chile); Department of Particle Physics, Tel Aviv University, Tel Aviv 69978 (Israel)

2010-10-01

119

NASA Astrophysics Data System (ADS)

Plane-wave solutions of the elastodynamic equations of motion, which yield slowness and group-velocity diagrams, are presently discussed for transversely isotropic materials, using a coordinate-free approach. The propagation of Gaussian wave packets in unidirectional homogeneous and layered structures is then calculated for arbitrary layer orientations. The results are presented as time-domain wavefront snapshots. An integral representation of Green's functions is given for the transversely-isotropic medium, via spatial Fourier transforms apposite to diffraction tomography.

Spies, M.; Fellinger, P.; Langenberg, K. J.

120

Quantum Corral Wave-function Engineering

NASA Astrophysics Data System (ADS)

We present a theoretical method for the design and optimization of quantum corrals[1] with specific electronic properties. Taking advantage that spins are subject to a RKKY interaction that is directly controlled by the scattering of the quantum corral, we design corral structures that reproduce spin Hamiltonians with coupling constants determined a priori[2]. We solve exactly the bi-dimensional scattering problem for each corral configuration within the s-wave approximation[3] and subsequently the geometry of the quantum corral is optimized by means of simulated annealing[4] and genetic algorithms[5]. We demonstrate the possibility of automatic design of structures with complicated target electronic properties[6]. This work was performed under the auspices of the US Department of Energy by the University of California at the LLNL under contract no W-7405-Eng-48. [1] M. F. Crommie, C. P. Lutz and D. M. Eigler, Nature 403, 512 (2000) [2] D. P. DiVincenzo et al., Nature 408, 339 (2000) [3] G. A. Fiete and E. J. Heller, Rev. Mod. Phys. 75, 933 (2003) [4] M. R. A. T. N. Metropolis et al., J. Chem. Phys. 1087 (1953) [5] E. Aarts and J. K. Lenstra, eds. Local search in combinatorial problems (Princeton University Press, 1997) [6] A. A. Correa, F. Reboredo and C. Balseiro, Phys. Rev. B (in press).

Correa, Alfredo; Reboredo, Fernando; Balseiro, Carlos

2005-03-01

121

B meson wave function in kT factorization

NASA Astrophysics Data System (ADS)

We study the asymptotic behavior of the B meson wave function in the framework of kT factorization theorem. We first construct a definition of the kT-dependent B meson wave function, which is free of light-cone divergences. Next-to-leading-order corrections are then calculated based on this definition. The treatment of different types of logarithms in the above corrections, including the Sudakov logarithms, and those depending on a renormalization scale and on an infrared regulator, is summarized. The criticism raised in the literature on our resummation formalism and Sudakov effect is responded. We show that the B meson wave function remains normalizable after taking into account renormalization-group evolution effects, contrary to the observation derived in the collinear factorization theorem.

Li, Hsiang-Nan; Liao, Huei-Shih

2004-10-01

122

B meson wave function in k{sub T} factorization

We study the asymptotic behavior of the B meson wave function in the framework of k{sub T} factorization theorem. We first construct a definition of the k{sub T}-dependent B meson wave function, which is free of light-cone divergences. Next-to-leading-order corrections are then calculated based on this definition. The treatment of different types of logarithms in the above corrections, including the Sudakov logarithms, and those depending on a renormalization scale and on an infrared regulator, is summarized. The criticism raised in the literature on our resummation formalism and Sudakov effect is responded. We show that the B meson wave function remains normalizable after taking into account renormalization-group evolution effects, contrary to the observation derived in the collinear factorization theorem.

Li Hsiangnan [Institute of Physics, Academia Sinica, Taipei, Taiwan 115 (China); Department of Physics, National Cheng-Kung University, Tainan, Taiwan 701 (China); Liao, Huei-Shih [Institute of Physics, Academia Sinica, Taipei, Taiwan 115 (China)

2004-10-01

123

Multi-time scale simulation for impact systems: from wave propagation to rigid-body motion

Summary ?Impact response encompasses a variety of complicated dynamic effects including wave propagation, structural vibrations and\\u000a rigid-body motion. For efficient simulation of impact response with sufficient accuracy, the methods of wave propagation and\\u000a multibody systems should be combined. This paper deals with an adaptive simulation of impact response during the transition\\u000a from wave propagation to rigid-body motion. For modeling structural vibrations,

B. Hu; W. Schiehlen

2003-01-01

124

Wave-function recombination instability in cold-atom interferometers

NASA Astrophysics Data System (ADS)

Cold-atom interferometers use guiding potentials that split the wave function of the Bose-Einstein condensate and then recombine it. We present a theoretical analysis of the wave-function recombination instability that is due to the weak nonlinearity of the condensate. It is most pronounced when the accumulated phase difference between the arms of the interferometer is close to an odd multiple of ? and consists in exponential amplification of the weak ground state mode by the strong first excited mode. The instability exists for both trapped-atom and beam interferometers.

Stickney, James A.; Zozulya, Alex A.

2002-11-01

125

Charmed quark component of the photon wave function

We determine the c-anti-c component of the photon wave function on the basis of (i) the data on the transitions e+ e- -> J\\/psi(3096), psi(3686), psi(4040), psi(4415), (ii) partial widths of the two-photon decays eta_{c0}(2979), chi_{c0}(3415), chi_{c2}(3556) -> gamma-gamma, and (iii) wave functions of the charmonium states obtained by solving the Bethe-Salpeter equation for the c-anti-c system. Using the obtained

V. V. Anisovich; L. G. Dakhno; V. N. Markov; V. A. Nikonov; A. V. Sarantsev

2005-01-01

126

Charmed quark component of the photon wave function

We determine the \\u000a $$c\\\\bar c$$\\u000a component of the photon wave function on the basis of (i) the data on the transitions e\\u000a +\\u000a e\\u000a ? ? J\\/?(3096), ?(3686), ?(4040), ?(4415), (ii) partial widths of the two-photon decays ?\\u000a \\u000a c0(2979), ?\\u000a \\u000a c0(3415), ?\\u000a \\u000a c2(3556) ? ??, and (iii) wave functions of the charmonium states obtained by solving the Bethe-Salpeter equation for

V. V. Anisovich; L. G. Dakhno; V. N. Markov; V. A. Nikonov; A. V. Sarantsev

2005-01-01

127

Many-body wave function in a dipole blockade configuration

We report the results of simulations of the many atom wave function when a cold gas is excited to highly excited states. We simulated the many body wave function by direct numerical solution of Schroedinger's equation. We investigated the fraction of atoms excited and the correlation of excited atoms in the gas for different types of excitation when the blockade region was small compared to the sample size. We also investigated the blockade effect when the blockade region is comparable to the sample size to determine the sensitivity of this system and constraints for quantum information.

Robicheaux, F.; Hernandez, J. V. [Department of Physics, Auburn University, Alabama 36849-5311 (United States)

2005-12-15

128

Transverse instability of a plane front of fast impact ionization waves

The transverse instability of a plane front of fast impact ionization waves in p{sup +}-n-n{sup +} semiconductor structures with a finite concentration of donors N in the n layer has been theoretically analyzed. It is assumed that the high velocity u of impact ionization waves is ensured owing to the avalanche multiplication of the uniform background of electrons and holes whose concentration {sigma}{sub b} ahead of the front is high enough for the continuum approximation to be applicable. The problem of the calculation of the growth rate s of a small harmonic perturbation with wavenumber k is reduced to the eigenvalue problem for a specific homogeneous Volterra equation of the second kind containing the sum of double and triple integrals of an unknown eigenfunction. This problem has been solved by the method of successive approximations. It has been shown that the function s(k) for small k values increases monotonically in agreement with the analytical theory reported in Thermal Engineering 58 (13), 1119 (2011), reaches a maximum s{sub M} at k = k{sub M}, then decreases, and becomes negative at k > k{sub 01}. This behavior of the function s(k) for short-wavelength perturbations is due to a decrease in the distortion of the field owing to a finite thickness of the space charge region of the front and 'smearing' of perturbation of concentrations owing to the transverse transport of charge carriers. The similarity laws for perturbations with k Greater-Than-Or-Equivalent-To k{sub M} have been established: at fixed {sigma}{sub b} values and the maximum field strength on the front E{sub 0M}, the growth rate s depends only on the ratio k/N and the boundary wavenumber k{sub 01} {proportional_to} N. The parameters s{sub M}, k{sub M}, and k{sub 01}, which determine the perturbation growth dynamics and the upper boundary of the instability region for impact ionization waves, have been presented as functions of E{sub 0M}. These dependences indicate that the model of a plane impact ionization wave is insufficient for describing the operation of avalanche voltage sharpers and that fronts of fast streamers in the continuum approximation should be stable with respect to transverse perturbations in agreement with the previously reported numerical simulation results. The results have been confirmed by the numerical simulation of the evolution of small harmonic perturbations of the steady-state plane impact ionization wave.

Kyuregyan, A. S., E-mail: ask@vei.ru [All-Russia Institute of Electrical Engineering (Russian Federation)

2012-05-15

129

Complete Reconstruction of the Wave Function of a Reacting Molecule by Four-Wave Mixing Spectroscopy

NASA Astrophysics Data System (ADS)

Probing the real time dynamics of a reacting molecule remains one of the central challenges in chemistry. Here we show how the time-dependent wave function of an excited-state reacting molecule can be completely reconstructed from resonant coherent anti-Stokes Raman spectroscopy. The method assumes knowledge of the ground potential but not of any excited potential. The excited-state potential can in turn be constructed from the wave function. The formulation is general for polyatomics and applies to bound as well as dissociative excited potentials. We demonstrate the method on the Li2 molecule.

Avisar, David; Tannor, David J.

2011-04-01

130

National Technical Information Service (NTIS)

We develop methodology for performing time dependent quantum mechanical calculations by representing the wave function as a sum of Gaussian wave packets (GWP), each characterized by a set of parameters such as width, position, momentum and phase. The prob...

B. Jackson H. Metiu R. Heather S. I. Sawada

1985-01-01

131

Surface acoustic wave depth profiling of a functionally graded material

The potential and limitations of Rayleigh wave spectroscopy to characterize the elastic depth profile of heterogeneous functional gradient materials are investigated by comparing simulations of the surface acoustic wave dispersion curves of different profile-spectrum pairs. This inverse problem is shown to be quite ill posed. The method is then applied to extract information on the depth structure of a glass-ceramic (alumina) functionally graded material from experimental data. The surface acoustic wave analysis suggests the presence of a uniform coating region consisting of a mixture of Al{sub 2}O{sub 3} and glass, with a sharp transition between the coating and the substrate. This is confirmed by scanning electron microscope with energy dispersive x-ray analysis.

Goossens, Jozefien; Leclaire, Philippe; Xu Xiaodong; Glorieux, Christ; Martinez, Loic; Sola, Antonella; Siligardi, Cristina; Cannillo, Valeria; Van der Donck, Tom; Celis, Jean-Pierre [Laboratorium voor Akoestiek en Thermische Fysica, Departement Natuurkunde en Sterrenkunde, Katholieke Universiteit Leuven, PO 2416, Celestijnenlaan 200D, B-3001 Leuven (Belgium); Equipe Circuit Instrumentation et Modelisation en Electronique (ECIME) IUP GE, Universite de Cergy, Rue de Eragny, Neuville sur Oise, 95031 Cergy Pontoise Cedex (France); Dipartimento di Ingegneria dei Materiali e dell' Ambiente, University of Modena and Reggio Emilia, Via Vignolese 905, 41100 Modena (Italy); Departement Department of Metallurgy and Materials Engineering (MTM), Katholieke Universiteit Leuven, PO 2450, Kasteelpark Arenberg 44, B-3001 Heverlee (Belgium)

2007-09-01

132

Oblique propagation, wave particle interaction and particle distribution function

NASA Astrophysics Data System (ADS)

Recent results from the Cluster mission have stimulated theoretical investigations and simulations to explain ion distribution functions observed in the quasi-perp bow shock. High-time resolution observations have revealed distributions of gyrating ions that are gyrophase-bunched. When not produced at the shock, such distributions are believed to be resulting from interactions between field-aligned beams and low frequency beamdriven waves . The Conventional models used to account for such distributions assume that the waves are purely transverse, and that they propagate parallel to the ambient magnetic eld. However observations indicate that these waves are propagating obliquely with respect to the ambient magnetic eld [Meziane et al., 2001]. A theoretical investigation of the non-relativistic wave-particle interaction in a background magnetic eld with the electromagnetic wave propagating obliquely has been addressed previously, resulting in a dynamical system describing the wave interaction with a single ion in the absence of dissipation mechanisms. [Hamza et al., 2005] This dynamical system has been numerically integrated to construct the ion distribution functions by seeding the particles with di erent initial conditions. We compute the particle orbits and simulate the time evolution of the distribution functions based on Liouville's theorem of phase space density conservation. It will be shown that the trapping which is due to the oblique propagation of the wave, gives an explanation for gyrophase-bunching and unstable distributions in velocity space which could trigger instabilities such as firehose and mirror. Therefore this exercise provide insights on the particle dynamics and onset of waves away from the shock. Meziane, K., C. Mazelle, R.P. Lin, D. LeQueau, D.E. Larson, G.K. Parks, R.P. Lepping (2001), Three dimensional observations of gyrating ions distributions far upstream from the Earth's bow shock and their association with low-frequency waves, J. Geophys. Res. 106, 5731 Hamza, A. M., K. Meziane, and C. Mazelle (2006), Oblique propagation and nonlinear wave particle processes, J. Geophys. Res., 111, A04104

Osmane, Adnane; Hamza, A. M.; Meziane, Karim

133

Interpreting the Quantum Wave Function in Terms of 'Interacting Faculties'

In this article we discuss the problem of finding an interpretation of quantum mechanics which provides an objective account of physical reality. In the first place we discuss the problem of interpretation and analyze the importance of such an objective account in physics. In this context we present the problems which arise when interpreting the quantum wave function within the

Christian de Ronde

2007-01-01

134

BETA DECAY THEORY USING EXACT ELECTRON RADIAL WAVE FUNCTIONS

A modified formulation of the theory of beta decay is presented, in ; which exact electron radial wave functions for an extended nuclear charge ; distribution are used. The resulting formulas are suitable for accurate ; application as well as for a qualitative demonstration of the features of beta ; decay. The connection between spectrum shape and electron polarization can

Buehring

1963-01-01

135

The Schrodinger Wave Functional and S-branes

In this paper we will consider the minisuperspace approach to S-branes dynamics in the Schrodinger picture description. Time-evolution of vacuum wave functional for quantum field theory on S-brane is studied. Open string pair produc- tion is calculated. The analysis of density matrix for mixed states is also performed.

J. Klusoÿn

136

Photon wave function: A covariant formulation and equivalence with QED

We discuss the limits of the photon wave function (PWF) formalism, which is experiencing a revival these days as a result of new practical applications in photonics and quantum optics. We build a Dirac-like equation for the PWF written in a manifestly covariant form and show that, in the presence of charged matter fields, it reproduces the standard formulation of

Fabrizio Tamburini; Denise Vicino

2008-01-01

137

QCD Sum Rules for Pion Wave Function Revisited.

National Technical Information Service (NTIS)

We analyze new QCD sum rules for the pion wave function (WF) (phi)(sub (pi)) (x), obtained recently in the non-local vacuum condensates method for nondiagonal correlators, and suggest a new approach for extracting WF of (pi)-meson and the mass and WF of t...

A. P. Bakulev S. V. Mikhajlov

1994-01-01

138

Molecular Velocity Distribution Function Measurements in a Normal Shock Wave

Molecular velocity distribution functions have been measured throughout a normal, M = 1.59 helium shock wave that was formed in a low-density wind tunnel. The measurements were obtained by using the electron beam fluorescence technique. Throughout the shock transition, distributions of random velocities were observed from directions both parallel and perpendicular to the flow. Also, direct measurements were made of

E. P. Muntz; L. N. Harnett

1969-01-01

139

Monte Carlo wave-function method in quantum optics

We present a wave-function approach to the study of the evolution of a small system when it is coupled to a large reservoir. Fluctuations and dissipation originate in this approach from quantum jumps that occur randomly during the time evolution of the system. This approach can be applied to a wide class of relaxation operators in the Markovian regime, and

Klaus Mølmer; Yvan Castin; Jean Dalibard

1993-01-01

140

Gap Wave Propagation in Functionally Graded Piezoelectric Material Structures

Shear horizontal gap wave propagating between functionally graded piezoelectric material (FGPM) layer and a layered piezoelectric structure is investigated analytically. The electrically open conditions on strip surface are applied to solve this problem. The phase velocity can be numerically calculated for the electrically open case, with different thickness of the layer and wavenumber. The effect of the gradient variation about

Jianke Du; Kai Xian; Ji Wang

2007-01-01

141

Vector Meson Form Factors and Wave Functions from Holographic QCD

Based on the holographic dual model of QCD, we study 2- and 3-point functions of vector currents and derive form factors as well as wave functions for the vector mesons. As a result, generalized vector-meson dominance representation for form factors is obtained with a very specific VMD pattern. The calculated electric radius of the rho-meson is shown to be in a good agreement with predictions from lattice QCD.

Hovhannes Grigoryan; Anatoly Radyushkin

2007-10-10

142

A technique for estimating the ocean surface roughness probability density function from satellite altimeter data is presented. Results from the application of the technique to Geos 3 altimeter data demonstrate its ability to detect both large-scale and small-scale structural deviations from the Gaussian distribution. Knowledge of the surface roughness probability density enables a direct computation of significant wave height. Significant

R. W. Priester; L. S. Miller

1979-01-01

143

A technique for estimating the ocean surface roughness probability density function from satellite altimeter data is presented. Results from the application of the technique to Geos 3 altimeter data demonstrate its ability to detect both large-scale and small-scale structural deviations from the Gaussian distribution. Knowledge of the surface roughness probability density enables a direct computation of significant wave height. Significant

R. W. Priester; L. S. Miller

1979-01-01

144

USING PHOTON WAVE FUNCTION FOR THE TIME-DOMAIN ANALYSIS OF ELECTROMAGNETIC WAVE SCATTERING

In this paper, a generalized photon wave function (PWF) which is applicable to electromagnetic problems is introduced. The formulation treats the electromagnetics fields as quantum mechanical entities. The introduced PWF is especially useful for boundary- value problems. For instance,the reflection coefficient at a dielectric half space is calculated based on the concepts of PWF and quantum mechanics. With the proposed

Bahar Khadem-Hosseinieh; Y. Komijani; Reza Faraji-Dana; Mahmoud Shahabadi

2007-01-01

145

Eikonal approximation in AdS\\/CFT: Conformal partial waves and finite N four-point functions

We introduce the impact parameter representation for conformal field theory correlators of the form A??O1O2O1O2?. This representation is appropriate in the eikonal kinematical regime, and approximates the conformal partial wave decomposition in the limit of large spin and dimension of the exchanged primary. Using recent results on the two-point function ?O1O1?shock in the presence of a shock wave in anti-de

Lorenzo Cornalba; Miguel S. Costa; João Penedones; Ricardo Schiappa

2007-01-01

146

Critical Analysis of the Density Functional Theory Prediction of Enhanced Capillary Waves

NASA Astrophysics Data System (ADS)

We present a critical analysis of the density functional description for capillary wave fluctuations on free liquid surfaces. The proposal made by Mecke and Dietrich, [Phys. Rev. EPLEEE81063-651X 59, 6766 (1999)10.1103/PhysRevE.59.6766], to obtain the effective wave vector dependent surface tension, and their prediction of an enhanced regime of capillary waves at mesoscopic scales, has had a large impact including claims of experimental observation [Fradin , Nature (London)NATUAS0028-0836 403, 871 (2000)10.1038/35002533; Mora , Phys. Rev. Lett.PRLTAO0031-9007 90, 216101 (2003)10.1103/PhysRevLett.90.216101]. Our analysis shows that there is a qualitative problem in the convergence of the low q expansion used for that prediction, and that the assumed link between the equilibrium density functional description of the liquid surface and its capillary wave fluctuations leads always to the unphysical decrease of the surface tension for large wave vectors.

Tarazona, P.; Checa, R.; Chacón, E.

2007-11-01

147

The impact of the summer 2003 heat wave in Iberia: how should we measure it?

We present a new approach to improve the reliability of quantifying the impact of a heat wave on mortality rates. We show,\\u000a for the recent European summer 2003 heat wave, that the use of absolute maximum temperature values, or number of days above\\u000a a given threshold, can be misleading. Here, we have assessed the impact of the heat wave on

J. Díaz; R. García-Herrera; R. M. Trigo; C. Linares; M. A. Valente; J. M. De Miguel; E. Hernández

2006-01-01

148

Quantum Canonical Tensor Model and AN Exact Wave Function

NASA Astrophysics Data System (ADS)

Tensor models in various forms are being studied as models of quantum gravity. Among them the canonical tensor model has a canonical pair of rank-three tensors as dynamical variables, and is a pure constraint system with first-class constraints. The Poisson algebra of the first-class constraints has structure functions, and provides an algebraically consistent way of discretizing the Dirac first-class constraint algebra for general relativity. This paper successfully formulates the Wheeler-DeWitt scheme of quantization of the canonical tensor model; the ordering of operators in the constraints is determined without ambiguity by imposing Hermiticity and covariance on the constraints, and the commutation algebra of constraints takes essentially the same form as the classical Poisson algebra, i.e. is first-class. Thus one could consistently obtain, at least locally in the configuration space, wave functions of "universe" by solving the partial differential equations representing the constraints, i.e. the Wheeler-DeWitt equations for the quantum canonical tensor model. The unique wave function for the simplest nontrivial case is exactly and globally obtained. Although this case is far from being realistic, the wave function has a few physically interesting features; it shows that locality is favored, and that there exists a locus of configurations with features of beginning of universe.

Sasakura, Naoki

2013-08-01

149

Resonating valence bond wave functions and classical interacting dimer models.

We relate properties of nearest-neighbor resonating valence-bond (NNRVB) wave functions for SU(g) spin systems on two-dimensional bipartite lattices to those of fully packed interacting classical dimer models on the same lattice. The interaction energy can be expressed as a sum of n-body potentials V(n), which are recursively determined from the NNRVB wave function on finite subgraphs of the original lattice. The magnitude of the n-body interaction V(n) (n>1) is of order O(g(-(n-1))) for small g(-1). The leading term is a two-body nearest-neighbor interaction V2(g) favoring two parallel dimers on elementary plaquettes. For SU(2) spins, using our calculated value of V2(g=2), we find that the long-distance behavior of the bond-energy correlation function is dominated by an oscillatory term that decays as 1/|r|? with ??1.22. This result is in remarkable quantitative agreement with earlier direct numerical studies of the corresponding wave function, which give ??1.20. PMID:23004328

Damle, Kedar; Dhar, Deepak; Ramola, Kabir

2012-06-15

150

Phases of Augmented Hadronic Light-Front Wave Functions

It is an important question whether the final/initial state gluonic interactions which lead to naive-time-reversal-odd single-spin asymmetries and diffraction at leading twist can be associated in a definite way with the light-front wave function hadronic eigensolutions of QCD. We use light-front time-ordered perturbation theory to obtain augmented light-front wave functions which contain an imaginary phase which depends on the choice of advanced or retarded boundary condition for the gauge potential in light-cone gauge. We apply this formalism to the wave functions of the valence Fock states of nucleons and pions, and show how this illuminates the factorization properties of naive-time-reversal-odd transverse momentum dependent observables which arise from rescattering. In particular, one calculates the identical leading-twist Sivers function from the overlap of augmented light-front wavefunctions that one obtains from explicit calculations of the single-spin asymmetry in semi-inclusive deep inelastic lepton-polarized nucleon scattering where the required phases come from the final-state rescattering of the struck quark with the nucleon spectators.

Brodsky, Stanley J.; /SLAC; Pasquini, Barbara; /Pavia U. /INFN, Pavia; Xiao, Bo-Wen; /LBNL, NSD; Yuan, Feng; /LBNL, NSD /RIKEN BNL

2010-02-15

151

Electron number probability distributions for correlated wave functions.

Efficient formulas for computing the probability of finding exactly an integer number of electrons in an arbitrarily chosen volume are only known for single-determinant wave functions [E. Cances et al., Theor. Chem. Acc. 111, 373 (2004)]. In this article, an algebraic method is presented that extends these formulas to the case of multideterminant wave functions and any number of disjoint volumes. The derived expressions are applied to compute the probabilities within the atomic domains derived from the space partitioning based on the quantum theory of atoms in molecules. Results for a series of test molecules are presented, paying particular attention to the effects of electron correlation and of some numerical approximations on the computed probabilities. PMID:17362099

Francisco, E; Martín Pendás, A; Blanco, M A

2007-03-01

152

Interpreting the Quantum Wave Function in Terms of 'Interacting Faculties'

In this article we discuss the problem of finding an interpretation of\\u000aquantum mechanics which provides an objective account of physical reality. In\\u000athe first place we discuss the problem of interpretation and analyze the\\u000aimportance of such an objective account in physics. In this context we present\\u000athe problems which arise when interpreting the quantum wave function within the

Christian de Ronde

2007-01-01

153

Analytical wave functions for atomic quantum-defect theory

We present an exactly solvable effective potential that reproduces atomic spectra in the limit of exact quantum-defect theory, i.e., the limit in which, for a fixed l, the principal quantum number is modified by a constant: n*=n-delta(l). Transition probabilities for alkali atoms are calculated using the analytical wave functions obtained and agree well with accepted values. This allows us to

V. Alan Kostelecký; Michael Martin Nieto

1985-01-01

154

Energy-Dependent Potential and Normalization of Wave Function

NASA Astrophysics Data System (ADS)

The problem of normalization related to energy-dependent potentials is examined in the context of the path integral approach, and a justification is given. As examples, the harmonic oscillator and the hydrogen atom (radial) where, respectively the frequency and the Coulomb's constant depend on energy, are considered and their propagators determined. From their spectral decomposition, we have found that the wave functions extracted are correctly normalized.

Benchikha, A.; Chetouani, L.

2013-06-01

155

Solutions of the Maxwell equations and photon wave functions

Properties of six-component electromagnetic field solutions of a matrix form of the Maxwell equations, analogous to the four-component solutions of the Dirac equation, are described. It is shown that the six-component equation, including sources, is invariant under Lorentz transformations. Complete sets of eigenfunctions of the Hamiltonian for the electromagnetic fields, which may be interpreted as photon wave functions, are given

Peter J. Mohr; Peter J

2010-01-01

156

Interaction between light and matter: a photon wave function approach

The Bialynicki-Birula-Sipe photon wave function formalism is extended to include the interaction between photons and continuous non-absorptive media. When the second quantization of this formalism is introduced, a new method for describing the quantum interactions between light and matter emerges. As an example of the application of the method, an expression for the quantum state of the twin photons generated

Pablo L. Saldanha; C. H. Monken

2011-01-01

157

Wave characteristics in functionally graded piezoelectric hollow cylinders

Based on linear three-dimensional piezoelasticity, the Legendre orthogonal polynomial series expansion approach is used for\\u000a determining the wave characteristics in hollow cylinders composed of the functionally graded piezoelectric materials (FGPM)\\u000a with open circuit. The displacement and electric potential components, expanded in a series of Legendre polynomials, are introduced\\u000a into the governing equations along with position-dependent material constants so that the

Yu Jiangong; Wu Bin; Chen Guoqiang

2009-01-01

158

The impact of heat waves on children's health: a systematic review.

Young children are thought to be particularly sensitive to heat waves, but relatively less research attention has been paid to this field to date. A systematic review was conducted to elucidate the relationship between heat waves and children's health. Literature published up to August 2012 were identified using the following MeSH terms and keywords: "heatwave", "heat wave", "child health", "morbidity", "hospital admission", "emergency department visit", "family practice", "primary health care", "death" and "mortality". Of the 628 publications identified, 12 met the selection criteria. The existing literature does not consistently suggest that mortality among children increases significantly during heat waves, even though infants were associated with more heat-related deaths. Exposure to heat waves in the perinatal period may pose a threat to children's health. Pediatric diseases or conditions associated with heat waves include renal disease, respiratory disease, electrolyte imbalance and fever. Future research should focus on how to develop a consistent definition of a heat wave from a children's health perspective, identifying the best measure of children's exposure to heat waves, exploring sensitive outcome measures to quantify the impact of heat waves on children, evaluating the possible impacts of heat waves on children's birth outcomes, and understanding the differences in vulnerability to heat waves among children of different ages and from different income countries. Projection of the children's disease burden caused by heat waves under climate change scenarios, and development of effective heat wave mitigation and adaptation strategies that incorporate other child protective health measures, are also strongly recommended. PMID:23525899

Xu, Zhiwei; Sheffield, Perry E; Su, Hong; Wang, Xiaoyu; Bi, Yan; Tong, Shilu

2013-03-23

159

The impact of heat waves on children's health: a systematic review

NASA Astrophysics Data System (ADS)

Young children are thought to be particularly sensitive to heat waves, but relatively less research attention has been paid to this field to date. A systematic review was conducted to elucidate the relationship between heat waves and children's health. Literature published up to August 2012 were identified using the following MeSH terms and keywords: "heatwave", "heat wave", "child health", "morbidity", "hospital admission", "emergency department visit", "family practice", "primary health care", "death" and "mortality". Of the 628 publications identified, 12 met the selection criteria. The existing literature does not consistently suggest that mortality among children increases significantly during heat waves, even though infants were associated with more heat-related deaths. Exposure to heat waves in the perinatal period may pose a threat to children's health. Pediatric diseases or conditions associated with heat waves include renal disease, respiratory disease, electrolyte imbalance and fever. Future research should focus on how to develop a consistent definition of a heat wave from a children's health perspective, identifying the best measure of children's exposure to heat waves, exploring sensitive outcome measures to quantify the impact of heat waves on children, evaluating the possible impacts of heat waves on children's birth outcomes, and understanding the differences in vulnerability to heat waves among children of different ages and from different income countries. Projection of the children's disease burden caused by heat waves under climate change scenarios, and development of effective heat wave mitigation and adaptation strategies that incorporate other child protective health measures, are also strongly recommended.

Xu, Zhiwei; Sheffield, Perry E.; Su, Hong; Wang, Xiaoyu; Bi, Yan; Tong, Shilu

2013-03-01

160

When waves break against seawalls, vertical breakwaters, piers or jetties, they abruptly transfer their momentum into the structure. This energy transfer is always spectacular and perpetually unrepeatable but can also be very violent and affect the stability and the integrity of coastal structures. Over the last 15years, increasing awareness of wave-impact induced structural failures of maritime structures has emphasised the

Giovanni Cuomo; Rodolfo Piscopia; William Allsop

2011-01-01

161

Joint inversion of receiver function and surface wave dispersion observations

NASA Astrophysics Data System (ADS)

We implement a method to invert jointly teleseismic P-wave receiver functions and surface wave group and phase velocities for a mutually consistent estimate of earth structure. Receiver functions are primarily sensitive to shear wave velocity contrasts and vertical traveltimes, and surface wave dispersion measurements are sensitive to vertical shear wave velocity averages. Their combination may bridge resolution gaps associated with each individual data set. We formulate a linearized shear velocity inversion that is solved using a damped least-squares scheme that incorporates a priori smoothness constraints for velocities in adjacent layers. The data sets are equalized for the number of data points and physical units in the inversion process. The combination of information produces a relatively simple model with a minimal number of sharp velocity contrasts. We illustrate the approach using noise-free and realistic noise simulations and conclude with an inversion of observations from the Saudi Arabian Shield. Inversion results for station SODA, located in the Arabian Shield, include a crust with a sharp gradient near the surface (shear velocity changing from 1.8 to 3.5kms-1 in 3km) underlain by a 5-km-thick layer with a shear velocity of 3.5kms-1 and a 27-km-thick layer with a shear velocity of 3.8kms-1, and an upper mantle with an average shear velocity of 4.7kms-1. The crust-mantle transition has a significant gradient, with velocity values varying from 3.8 to 4.7kms-1 between 35 and 40km depth. Our results are compatible with independent inversions for crustal structure using refraction data.

Julià, J.; Ammon, C. J.; Herrmann, R. B.; Correig, A. M.

2000-10-01

162

Improved variational many-body wave function in light nuclei

We propose and implement a simple method for improving the variational wave function of a many-body system. We have obtained a significant improvement in the binding energies, wave functions, and variance for the light nuclei {sup 3}H, {sup 4}He, and {sup 6}Li, using the fully realistic Argonne (AV{sub 18}) two-body and Urbana-IX (UIX) three-body interactions. The energy of {sup 4}He was improved by about 0.2 MeV and the {sup 6}Li binding energy was increased by {approx_equal}1.7 MeV compared to earlier variational Monte Carlo results. The latter result demonstrates the significant progress achieved by our method, and detailed analyses of the improved results are given. With central interactions the results are found to be in agreement with the 'exact' calculations. Our study shows that the relative error in the many-body wave functions, compared to two-body pair correlations, increases rapidly at least proportionally to the number of pairs in the system. However, this error does not increase indefinitely since the pair interactions saturate owing to convergence of cluster expansion.

Usmani, Q. N.; Anwar, K. [Institute of Engineering Mathematics, University Malaysia Perlis (Malaysia); Singh, A. [Department of Physics, School of Technology, Kalinga Institute of Industrial Technology, Bhubaneswar 751 024 (India); Rawitscher, G. [Department of Physics, University of Connecticut, Storrs, Connecticut 06269-3046 (United States)

2009-09-15

163

NASA Astrophysics Data System (ADS)

Exact finite range distorted-wave Born approximation analysis of the ground state reactions 208Pb(p,t)206Pb and 18O(p,t)16O are presented. The calculations are carried out using a realistic triton wave function comprising a spatially symmetric S and mixed symmetric S' and D states. The transfer interaction is treated consistently with the interaction used in obtaining the triton wave function. The use of a realistic wave function and transfer potential yields improved agreement between experimental and theoretical angular distributions. Calculations using the wave function of the transferred neutron pair suggest it is possible to explain both the absolute magnitude and shape of the angular distribution for these transitions. NUCLEAR REACTIONS (p,t), distorted-wave Born approximation analyses.

Werby, M. F.; Strayer, M. R.; Nagarajan, M. A.

1980-06-01

164

Gutzwiller-Jastrow wave functions for the 1/[ital r] Hubbard model

In this work, we study the wave functions of the one-dimensional 1/[ital r] Hubbard model in the strong-interaction limit [ital U]=[infinity]. A set of Gutzwiller-Jastrow wave functions are shown to be eigenfunctions of the Hamiltonian. The entire excitation spectrum and the thermodynamics are also studied in terms of more generalized Jastrow wave functions. For the wave functions and integrability conditions at finite on-site energy, further investigations are needed.

Wang, D.F. (Joseph Henry Laboratories of Physics, Princeton University, Princeton, New Jersey 08544 (United States)); Zhong, Q.F. (International School for Advanced Study, Via Beirut 4, 34014 Trieste (Italy)); Coleman, P. (Serin Physics Laboratory, Rutgers University, P. O. Box 849, Piscataway, New Jersey 08854 (United States))

1993-09-15

165

Pion and photon light-cone wave functions from the instanton vacuum

The leading-twist wave functions of the pion and the photon at a low normalization point are calculated in the effective low-energy theory derived from the instanton vacuum. The pion wave function is found to be close to the asymptotic one, consistent with the recent CLEO measurements. The photon wave function is nonzero at the end points. This different behavior is

V. Yu. Petrov; M. V. Polyakov; R. Ruskov; C. Weiss; K. Goeke

1999-01-01

166

Baryon wave functions and cross sections for photon annihilation to baryon pairs

The first few moments of the wave functions for Delta's and Omega are evaluated by QCD sum rules. Model wave functions are constructed based on these moments. Perturbative QCD predictions of cross sections for gammagamma --> Delta++Delta++ and gammagamma --> OmegaOmega are obtained by integrating the quark scattering amplitudes over these wave functions. The ratio of gammagamma --> Delta++Delta++ and

G. R. Farrar; H. Zhang; A. A. Ogloblin; I. R. Zhitnitsky

1989-01-01

167

A wave propagation model for the high velocity impact response of a composite sandwich panel

A solution methodology to predict the residual velocity of a hemispherical-nose cylindrical projectile impacting a composite sandwich panel at high velocity is presented. The term high velocity impact is used to describe impact scenarios where the projectile perforates the panel and exits with a residual velocity. The solution is derived from a wave propagation model involving deformation and failure of

Michelle S. Hoo Fatt; Dushyanth Sirivolu

2010-01-01

168

The impact energy of a moored tanker under the action of regular waves

The influence that factors such as mooring line conditions, fender arrangements, dolphin arrangements, degree of ship loading, waves of long period, wave direction, and wind on the impact energy of a moored tanker were studied. Based on systematic test data, a semi-empirical formula was developed to calculate the impact energy of the moored ship on the berthing facilities under the action of regular waves. It was shown by experiment that this method is suitable for calculating the impact energy of moored ships of capacities as great as 200 X 10/sup 3/ t.

Yu-Cheng Li

1982-09-01

169

Spin-orbit interaction with nonlinear wave functions.

The computation of the spin-orbit interaction is discussed for electronic wave functions expressed in the new nonlinear expansion form. This form is based on spin eigenfunctions using the graphical unitary group approach (GUGA). The nodes of a Shavitt graph in GUGA are connected by arcs, and a Configuration State Function (CSF) is represented as a walk along arcs from the vacuum node to a head node. The wave function is a linear combination of product functions each of which is a linear combination of all CSFs, wherein each CSF coefficient is a product of nonlinear arc factors. When the spin-orbit interaction is included the Shavitt graph is a union of single-headed Shavitt graphs each with the same total number of electrons and orbitals. Thus spin-orbit Shavitt graphs are multiheaded. For full-CI multiheaded Shavitt graphs, analytic expressions are presented for the number of walks, the number of nodes, the number of arcs, and the number of node pairs in the associated auxiliary pair graph.

Brozell, S. R.; Shepard, R.; Zhang, Z.; Stanford Univ.

2007-12-01

170

Propagation of impact-induced shock waves in porous sandstone using mesoscale modeling

NASA Astrophysics Data System (ADS)