Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 22 of 22

Full-Text Articles in Physical Sciences and Mathematics

Q2 Evolution Of The Generalized Gerasimov-Drell-Hearn Integral For The Neutron Using A 3He Target, M. Amarian, L. Auerbach, T. Avertett, J. Berthot, P. Bertin, W. Bertozzi, T. Black, E. Brash, D. Brown, E. Burtin, J. R. Calarco, G. D. Cates, Z. Chai, J. P. Chen, Seonho Choi, E. Chudakov, E. Cisbani, C. W. De Jager, A. Deur, R. Disalvo, S. Dieterich, P. Djawotho, M. Finn, K. Fissum, H. Fovieille, S. Frullani, H. Gao, J. Gao, F. Garibaldi, A. Gasparian, S. Gilad, R. Gilman, A. Glamazdin, C. Glashausser, E. Goldberg, J. Gomez, V. Gorbenko, J. O. Hansen, F. W. Hersman, R. Holmes, G. M. Huber, E. W. Hughes, T. B. Humensky, S. Incerti, M. Iodice, S. Jensen, X. Jiang, C. Jones, G. M. Jones, M. Jones, C. Jutier, A. Ketikyan, I. Kominis, W. Korsch, K. Kramer, K. S. Kumar, G. Kumbartzki, M. Kuss, Enkeleida K. Lakuriqi, G. Laveissiere, J. Lerose, M. Liang, N. Liyanage, G. Lolos, S. Mavlov, J. Marroncle, K. Mccormick, R. Mckeown, Z. E. Meziani, R. Michaels, J. Mitchell, Z. Papandreou, T. Pavlin, G. G. Petratos, D. Pripstein, D. Prout, R. Ransome, Y. Roblin, D. Rowntree, M. Rvachev, F. Sabatie, A. Saha, K. Slifer, P. A. Souder, T. Saito, S. Strauch, R. Suleiman, K. Takahashi, S. Teijiro, L. Todor, H. Tsubota, H. Ueno, G. Urciuoli, R. Van De Meer, P. Vernin, H. Voskanian, B. Wojtsekhowski, F. Xiong, W. Xu, J. C. Yang, B. Zhang, P. Zolnierczuk Nov 2002

Q2 Evolution Of The Generalized Gerasimov-Drell-Hearn Integral For The Neutron Using A 3He Target, M. Amarian, L. Auerbach, T. Avertett, J. Berthot, P. Bertin, W. Bertozzi, T. Black, E. Brash, D. Brown, E. Burtin, J. R. Calarco, G. D. Cates, Z. Chai, J. P. Chen, Seonho Choi, E. Chudakov, E. Cisbani, C. W. De Jager, A. Deur, R. Disalvo, S. Dieterich, P. Djawotho, M. Finn, K. Fissum, H. Fovieille, S. Frullani, H. Gao, J. Gao, F. Garibaldi, A. Gasparian, S. Gilad, R. Gilman, A. Glamazdin, C. Glashausser, E. Goldberg, J. Gomez, V. Gorbenko, J. O. Hansen, F. W. Hersman, R. Holmes, G. M. Huber, E. W. Hughes, T. B. Humensky, S. Incerti, M. Iodice, S. Jensen, X. Jiang, C. Jones, G. M. Jones, M. Jones, C. Jutier, A. Ketikyan, I. Kominis, W. Korsch, K. Kramer, K. S. Kumar, G. Kumbartzki, M. Kuss, Enkeleida K. Lakuriqi, G. Laveissiere, J. Lerose, M. Liang, N. Liyanage, G. Lolos, S. Mavlov, J. Marroncle, K. Mccormick, R. Mckeown, Z. E. Meziani, R. Michaels, J. Mitchell, Z. Papandreou, T. Pavlin, G. G. Petratos, D. Pripstein, D. Prout, R. Ransome, Y. Roblin, D. Rowntree, M. Rvachev, F. Sabatie, A. Saha, K. Slifer, P. A. Souder, T. Saito, S. Strauch, R. Suleiman, K. Takahashi, S. Teijiro, L. Todor, H. Tsubota, H. Ueno, G. Urciuoli, R. Van De Meer, P. Vernin, H. Voskanian, B. Wojtsekhowski, F. Xiong, W. Xu, J. C. Yang, B. Zhang, P. Zolnierczuk

Enkeleida K. Lakuriqi

We present data on the inclusive scattering of polarized electrons from a polarized 3He target at energies from 0.862 to 5.06 GeV, obtained at a scattering angle of 15.5°.Our data include measurements from the quasielastic peak, through the nucleon resonance region, and beyond, and were used to determine the virtual photon cross-section difference σ1/2-σ3/2. We extract the extended Gerasimov-Drell-Hearn integral for the neutron in the range of four-momentum transfer squared Q2 of 0.1-0.9 GeV2.


A Discrete Nonlinear Model With Substrate Feedback, Panos Kevrekidis, B. A. Malomed, A. R. Bishop Oct 2002

A Discrete Nonlinear Model With Substrate Feedback, Panos Kevrekidis, B. A. Malomed, A. R. Bishop

Panos Kevrekidis

We consider a prototypical model in which a nonlinear field (continuum or discrete) evolves on a flexible substrate which feeds back to the evolution of the main field. We identify the underlying physics and potential applications of such a model and examine its simplest one-dimensional Hamiltonian form, which turns out to be a modified Frenkel-Kontorova model coupled to an extra linear equation. We find static kink solutions and study their stability, and then examine moving kinks (the continuum limit of the model is studied too). We observe how the substrate effectively renormalizes properties of the kinks. In particular, a nontrivial …


On The Minimum Ropelength Of Knots And Links, Jason Cantarella, Robert B. Kusner, John M. Sullivan Jun 2002

On The Minimum Ropelength Of Knots And Links, Jason Cantarella, Robert B. Kusner, John M. Sullivan

Robert Kusner

The ropelength of a knot is the quotient of its length by its thickness, the radius of the largest embedded normal tube around the knot. We prove existence and regularity for ropelength minimizers in any knot or link type; these are C 1,1 curves, but need not be smoother. We improve the lower bound for the ropelength of a nontrivial knot, and establish new ropelength bounds for small knots and links, including some which are sharp.


On The Existence Of Multiple Positive Solutions For A Semilinear Problem In Exterior Domains, Yinbin Deng, Yi Li May 2002

On The Existence Of Multiple Positive Solutions For A Semilinear Problem In Exterior Domains, Yinbin Deng, Yi Li

Yi Li

In this paper, we study the existence and nonexistence of multiple positive solutions for problem where Ω=N\ω is an exterior domain in N, ωN is a bounded domain with smooth boundary, and N>2. μ⩾0, p>1 are some given constants. K(x) satisfies: K(x)∈Cαloc(Ω) and ∃C, ϵ, M>0 such that |K(x)|⩽C |x|l for any |x|⩾M, with l⩽ −2−ϵ. Some existence and …


Smaller Solutions For The Firing Squad, Amber Settle, Janos Simon Mar 2002

Smaller Solutions For The Firing Squad, Amber Settle, Janos Simon

Amber Settle

In this paper we improve the bounds on the complexity of solutions to the firing squad problem, also known as the firing synchronization problem. In the firing synchronization problem we consider a one-dimensional array of n identical finite automata. Initially all automata are in the same state except for one automaton designated as the initiator for the synchronization. Our results hold for the original problem, where the initiator may be located at either endpoint, and for the variant where any one of the automata may be the initiator, called the generalized problem. In both cases, the goal is to define …


Parallel Implementation Of The Bi-Cgstab Method With Block Red–Black Gauss–Seidel Preconditioner Applied To The Hermite Collocation Discretization Of Partial Differential Equations, Stephen Brill, George Pinder Feb 2002

Parallel Implementation Of The Bi-Cgstab Method With Block Red–Black Gauss–Seidel Preconditioner Applied To The Hermite Collocation Discretization Of Partial Differential Equations, Stephen Brill, George Pinder

Stephen H. Brill

We describe herein the parallel implementation of the Bi-CGSTAB method with a block red–black Gauss–Seidel (RBGS) preconditioner applied to the systems of linear algebraic equations that arise from the Hermite collocation discretization of partial differential equations in two spatial dimensions. The method is implemented on the Cray T3E, a parallel processing supercomputer. Speedup results are discussed.


Laplace Transform Of Spherical Bessel Functions, Andrei Ludu Jan 2002

Laplace Transform Of Spherical Bessel Functions, Andrei Ludu

Andrei Ludu

No abstract provided.


The Effects Of Item Parceling On Goodness-Of-Fit And Parameter Estimate Bias In Structural Equation Modeling, Deborah L. Bandalos Jan 2002

The Effects Of Item Parceling On Goodness-Of-Fit And Parameter Estimate Bias In Structural Equation Modeling, Deborah L. Bandalos

Deborah L Bandalos

No abstract provided.


On The Approximation Properties Of Partial Sums Of Trigonometric Fourier Series, Ushangi Goginava Jan 2002

On The Approximation Properties Of Partial Sums Of Trigonometric Fourier Series, Ushangi Goginava

Ushangi Goginava

No abstract provided.


On The Approximation Properties Of Cesàro Means Of Negative Order Of Walsh-Fourier Series, Ushangi Goginava Jan 2002

On The Approximation Properties Of Cesàro Means Of Negative Order Of Walsh-Fourier Series, Ushangi Goginava

Ushangi Goginava

No abstract provided.


On Thickness And Packing Density For Knots And Links, Robert Kusner Jan 2002

On Thickness And Packing Density For Knots And Links, Robert Kusner

Robert Kusner

We describe some problems, observations, and conjectures concerning density of the hexagonal packing of unit disks in R2.thickness and packing density of knots and links in S3 and R3. We prove the thickness of a nontrivial knot or link in S3 is no more than 4 , the thickness of a Hopf link. We also give arguments and evidence supporting the conjecture that the packing density of thick links in R3 or S3 is generally less than √12 , the density of the hexagonal packing of unit disks in R2.


Discrete Nonlinear Model With Substrate Feedback, P. G. Kevrekidis, B. A. Malomed, A. R. Bishop Jan 2002

Discrete Nonlinear Model With Substrate Feedback, P. G. Kevrekidis, B. A. Malomed, A. R. Bishop

Panos Kevrekidis

We consider a prototypical model in which a nonlinear field (continuum or discrete) evolves on a flexible substrate which feeds back to the evolution of the main field. We identify the underlying physics and potential applications of such a model and examine its simplest one-dimensional Hamiltonian form, which turns out to be a modified Frenkel-Kontorova model coupled to an extra linear equation. We find static kink solutions and study their stability, and then examine moving kinks (the continuum limit of the model is studied too). We observe how the substrate effectively renormalizes properties of the kinks. In particular, a nontrivial …


On The Reducibility Of Characteristic Varieties, Tom Braden Jan 2002

On The Reducibility Of Characteristic Varieties, Tom Braden

Tom Braden

We show that some monodromies in the Morse local systems of a conically stratified perverse sheaf imply that other Morse local systems for smaller strata do not vanish. This result is then used to explain the examples of reducible characteristic varieties of Schubert varieties given by Kashiwara and Saito in type A and by Boe and Fu for the Lagrangian Grassmannian.


A Smooth Space Of Tetrahedra, E Babson, Pe Gunnells, R Scott Jan 2002

A Smooth Space Of Tetrahedra, E Babson, Pe Gunnells, R Scott

Paul Gunnells

This is the pre-published version harvested from ArXiv. We construct a smooth symmetric compactification of the space of all labeled tetrahedra in 3.


Nonequivalent Statistical Equilibrium Ensembles And Refined Stability Theorems For Most Probable Flows, Richard S. Ellis, Kyle Haven, Bruce Turkington Jan 2002

Nonequivalent Statistical Equilibrium Ensembles And Refined Stability Theorems For Most Probable Flows, Richard S. Ellis, Kyle Haven, Bruce Turkington

Richard S. Ellis

Statistical equilibrium models of coherent structures in two-dimensional and barotropic quasi-geostrophic turbulence are formulated using canonical and microcanonical ensembles, and the equivalence or nonequivalence of ensembles is investigated for these models. The main results show that models in which the energy and circulation invariants are treated microcanonically give richer families of equilibria than models in which they are treated canonically. For each model, a variational principle that characterizes its equilibrium states is derived by large deviation techniques. An analysis of the two different variational principles resulting from the canonical and microcanonical ensembles reveals that their equilibrium states coincide if and …


Decomposition Of Pascal’S Kernels Mod PS, Richard P. Kubelka Jan 2002

Decomposition Of Pascal’S Kernels Mod PS, Richard P. Kubelka

Richard P. Kubelka

For a prime p we define Pascal's Kernel K(p,s) = [k(p,s)ij]∞i,j=0 as the infinite matrix satisfying k(p,s)ij = 1/px(i+jj) mod p if (i+jj) is divisible by ps and k(p,s)ij = 0 otherwise. While the individual entries of Pascal's Kernel can be computed using a formula of Kazandzidis that has been known for some time, our purpose here will be to use that formula to explain the global geometric patterns that occur in K(p,s). Indeed, if we consider the finite (truncated) versions of K(p,s), we find that they can be decomposed into superpositions of tensor products of certain primitive p x …


Stable Refinable Generators Of Shift Invariant Spaces With Certain Regularities And Vanishing Moments, Tian-Xiao He Dec 2001

Stable Refinable Generators Of Shift Invariant Spaces With Certain Regularities And Vanishing Moments, Tian-Xiao He

Tian-Xiao He

In this paper, we discuss the stable refinable functions that generate shift in variant (SI) spaces and possess the largest possible regularities and required vanishing moments. The stability of the corresponding complementary spaces is also discussed.


Logic, Optimization And Constraint Programming, John Hooker Dec 2001

Logic, Optimization And Constraint Programming, John Hooker

John Hooker

No abstract provided.


Spectra Of Composition Operators On The Bloch And Bergman Spaces, Karen Saxe, B. Maccluer Dec 2001

Spectra Of Composition Operators On The Bloch And Bergman Spaces, Karen Saxe, B. Maccluer

Karen Saxe

No abstract provided.


Asymptotically Constant Solutions Of Functional Difference Systems, William F. Trench Dec 2001

Asymptotically Constant Solutions Of Functional Difference Systems, William F. Trench

William F. Trench

No abstract provided.


Analysis And Classification Of Nonlinear Dispersive Evolution Equations In The Potential Representation, Andrei Ludu Dec 2001

Analysis And Classification Of Nonlinear Dispersive Evolution Equations In The Potential Representation, Andrei Ludu

Andrei Ludu

No abstract provided.


Dimensionality-Reducing Expansion, Boundary Type Quadrature Formulas, And The Boundary Element Method, Tian-Xiao He Dec 2001

Dimensionality-Reducing Expansion, Boundary Type Quadrature Formulas, And The Boundary Element Method, Tian-Xiao He

Tian-Xiao He

This paper discusses the connection between boundary quadrature formulas constructed by using solutions of partial differential equations and boundary element schemes.