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June 2007 arXiv papers — page 46

Showing 4,501–4,521 of 4,521 papers

  1. H. Kaneda, W. Kim, T. Onaka, T. Wada

    AKARI currently in space carries onboard a cryogenically-cooled lightweight telescope with silicon carbide mirrors. The wavefront error of the AKARI telescope obtained in laboratory measurements at 9 K showed that expected in-orbit imaging performance was diffraction-limited at a wavelength of 6.2 um. The AKARI telescope has a function of focus adjustment by

  2. Shin-itiro Goto

    We study which and how a periodic orbit in phase space links to both the largest Lyapunov exponent and the expectation values of macroscopic variables in a Hamiltonian system with many degrees of freedom. The model which we use in this paper is the discrete nonlinear Schrödinger equation. Using a method based on the modulational estimate of a periodic orbit,

  3. H. Kaneda, T. Suzuki, T. Onaka, Y. Doi

    Far-infrared (IR) images of the nearby Sb galaxy NGC2841 and the Sc galaxy NGC2976 at wavelengths of 65, 90, 140, and 160 um have been obtained with the Far-Infrared Surveyor (FIS) onboard AKARI. Both galaxies reveal similar morphologies of dust rings. They are, however, significantly different in the dust temperature: a cold (21 K) ring for NGC2841 and a wa

  4. Pankaj Mishra, Swarn Lata Singh, Jokhan Ram, Yashwant Singh

    In this paper we have presented the calculation of pair correlation functions in a nematic phase for a model of spherical particles with the long-range anisotropic interaction from the mean spherical approximation(MSA) and the Percus-Yevick (PY) integral equation theories. The results found from the MSA theory have been compared with those found analytically

  5. Tadashi Miyazaki

    We describe explicitly the whole structures of the $(g,K)$-modules of principal series representations of $Sp(3,R)$. We apply this result to determine the holonomic system characterizing those Whittaker functions.

  6. Kazunari Shima, Motomu Tsuda

    We show explicitly in two dimensional spacetime (d = 2) that the N = 2 Volkov-Akulov model is equivalent to the spontaneously broken linear supersymmetry (LSUSY) interacting gauge theory for N = 2 vector and N = 2 scalar supermultiplets. The local gauge interaction of LSUSY is induced by the specific composite structure of the auxiliary fields and the conseq

  7. A. S. Bradley, M. K. Olsen, S. A. Haine, J. J. Hope

    We propose a method for quantum state transfer from one atom laser beam to another via an intermediate optical field, using Raman incoupling and outcoupling techniques. Our proposal utilises existing experimental technologies to teleport macroscopic matter waves over potentially large distances without shared entanglement.

  8. Yong Seung Cho, Soon-Tae Hong

    We consider the path space of a curved manifold on which a point particle is introduced in a conservative physical system with constant total energy to formulate its action functional and geodesic equation together with breaks on the path. The second variation of the action functional is exploited to yield the geodesic deviation equation and to discuss the J

  9. Tamara S. Nunner, N. A. Sinitsyn, Mario F. Borunda, A. A. Kovalev

    The anomalous Hall effect in a magnetic two-dimensional electron gas with Rashba spin-orbit coupling is studied within the Kubo-Streda formalism in the presence of pointlike potential impurities. We find that all contributions to the anomalous Hall conductivity vanish to leading order in disorder strength when both chiral subbands are occupied. In the situat

  10. F. Xiang, E. Churazov, K. Dolag, V. Springel

    We consider the impact of thermal conduction in clusters of galaxies on the (unmagnetized) interface between a cold gaseous cloud and a hotter gas flowing over the cloud (the so-called cold front). We argue that near the stagnation point of the flow conduction creates a spatially extended layer of constant thickness $Δ$, where $Δ$ is of order $\sim\sqrt{kR/U

  11. N. M. H. Vaytet, T. J. O'Brien, A. P. Rushton

    High-resolution longslit Halpha spectra of the shell of the old nova DQ Her have been obtained with the William Herschel Telescope using the ISIS spectrograph. An equatorial expansion velocity of 370+/-14 km/s is derived from the spectra which, in conjunction with a narrowband Halpha image of the remnant, allows a distance estimate of 525+/-28 pc. An equator

  12. P. Colangelo, F. De Fazio, R. Ferrandes, S. Nicotri

    We briefly analyze aspects of open and hidden charm resonances, discussing in particular the mesons $D_{sJ}(2860)$ and X(3872).

  13. Ioannis Karatzas, Gordan Zitkovic

    We consider the problem of maximizing expected utility from consumption in a constrained incomplete semimartingale market with a random endowment process, and establish a general existence and uniqueness result using techniques from convex duality. The notion of asymptotic elasticity of Kramkov and Schachermayer is extended to the time-dependent case. By imp

  14. Tai-Kai Ng, Patrick A. Lee

    The charge dynamics of spin-liquid states described by U(1) gauge theory coupling to fermionic spinons is discussed in this paper. We find that the gapless spinons give rise to a power law optical conductivity inside the charge gap. The theory is applied to explain the unusual optical conductivity observed recently in the organic compound $κ-(BEDT-TTF)_2Cu_2

  15. Gordan Zitkovic

    We extend the Bipolar Theorem of Brannath and Schachermayer (1999) to the space of nonnegative cadlag supermartingales on a filtered probability space. We formulate the notion of fork-convexity as an analogue to convexity in this setting. As an intermediate step in the proof of our main result we establish a conditional version of the Bipolar theorem. In an

  16. Zhigang Wang, Ping Zhang

    Using the microscopic theory of the conserved spin current [Phys. Rev. Lett. \textbf{96}, 076604 (2006)], we investigate the spin Hall effect in the two dimensional electron gas system with a perpendicular magnetic field. The spin Hall conductance $σ_{μν}^{s}$ as a response to the electric field consists of two parts, i.e., the conventional part $σ_{μν}^{s0}

  17. Jing-Chao Chen

    In this paper, we propose a useful replacement for quicksort-style utility functions. The replacement is called Symmetry Partition Sort, which has essentially the same principle as Proportion Extend Sort. The maximal difference between them is that the new algorithm always places already partially sorted inputs (used as a basis for the proportional extension

  18. Yoshifusa Ita, Toshihiko Tanabe, Noriyuki Matsunaga, Yoshikazu Nakada

    We report preliminary results of AKARI observations of two globular clusters, NGC104 and NGC362. Imaging data covering areas of about 10x10 arcmin^2 centered on the two clusters have been obtained with InfraRed Camera (IRC) at 2.4, 3.2, 4.1, 7.0, 9.0, 11.0, 15.0, 18.0 and 24.0 mu. We used F11/F2 and F24/F7 flux ratios as diagnostics of circumstellar dust emi

  19. Seung Ki Baek, Petter Minnhagen, Beom Jun Kim

    We numerically investigate the nature of the phase transition of the XY model in the heptagonal lattice with the negative curvature, in comparison to other interaction structures such as a flat two-dimensional (2D) square lattice and a small-world network. Although the heptagonal lattice has a very short characteristic path length like the small-world networ

  20. Shin-ichi Sasa

    We study a large deviation functional of density fluctuation by analyzing stochastic non-linear diffusion equations driven by the difference between the densities fixed at the boundaries. By using a fundamental equality that yields the fluctuation theorem, we first relate the large deviation functional with a minimization problem. We then develop a perturbat

  21. Yevgeniy Kuznetsov

    Resolution of the cosmological constant problem based on Causal Set theory is discussed. It is argued that one should not observe any spacetime variations in cosmological constant if Causal Set approach is correct.