August 2000 arXiv papers — page 14

M. Brüggen, W. Hillebrandt

In this paper we present the results of numerical simulations of the Kelvin-Helmholtz instability in a stratified shear layer. This shear instability is believed to be responsible for extra mixing in differentially rotating stellar interiors and is the prime candidate to explain the abundance anomalies observed in many rotating stars. All mixing prescription

J. Rossa, M. Dietrich, S. J. Wagner

We present a high spatial and spectral resolution 2-D echelle spectrogram of the Narrow-Line Region in the Seyfert 2 galaxy NGC1386. This Seyfert galaxy was observed with CASPEC in the wavelength range 5270-7725 Angstrom which covers the H-alpha and the [N II] lines. With the use of spatially high resolved images taken with the WFPC2 aboard the Hubble Space

W. F. Kao, R. -T. Yu

The slowly decreasing rotational velocity of the Milky Way suggests the existence of the dark matter. One finds that the effect of the dark matter in a galaxy can be described by a $(2+1)$-dimensional fluid model. The stability analysis for the corresponding fluid model is discussed in details in this paper. It is found that the pressure term plays an import

T. J. W. Lazio, R. A. Gaume, M. J. Claussen

We report multi-epoch VLA H I absorption observations of the source 1741-038 (OT-068) before and during an extreme scattering event (ESE). Observations at four epochs, three during the ESE, were obtained. We find no changes in the equivalent width, maximum optical depth, or velocity of maximum optical depth during the ESE, but we do find a secular trend of d

David M. Goldberg

In this paper, we present a redshift space reconstruction scheme which is analogous to and extends the Perturbative Least Action (PLA) method described by Goldberg & Spergel (2000). We first show that this scheme is effective in reconstructing even nonlinear observations. We then suggest that by varying the cosmology to minimize the quadrupole moment of a re

R. A. Battye, R. Crittenden, J. Weller

Recent measurements of a peak in the angular power spectrum of the cosmic microwave background appear to suggest that geometry of the universe is close to being flat. But if other accepted indicators of cosmological parameters are also correct then the best fit model is marginally closed, with the peak in the spectrum at larger scales than in a flat universe

Carlos De Breuck, Huub Rottgering, George Miley, Wil van Breugel

We have compiled a sample of 165 radio galaxies from the literature to study the properties of the extended emission line regions and their interaction with the radio source over a large range of redshift 0<z<5.2. For each source, we have collected radio (size, lobe distance ratio and power) and spectroscopic parameters (luminosity, line width and equivalent

Benjamin J. Weiner, Stuart N. Vogel, T. B. Williams

We report results from a survey of high velocity clouds and the Magellanic Stream for faint, diffuse optical recombination emission lines. We detect H-alpha emission with surface brightness from 41 to 1680 milli-Rayleighs (mR) from HVCs, and from <40 to 1360 mR in the MS. A simple model for the photoionizing radiation emergent from the Galaxy, normalized to

Yasuhiro Shioya, Kenji Bekki

Recent observational studies on galaxies in distant clusters discovered a significant fraction of possible dusty starburst galaxies with the so-called `e(a)&#39; spectra that are characterized by strong H$δ$ absorption and relatively modest [OII] emission. We numerically investigate spectroscopic and photometric evolution of dusty starburst galaxies in order

Neal Dalal, Kim Griest

In light of recent evidence suggesting a nonzero present-day cosmological constant, Adams, Mbonye, & Laughlin (1999) have considered the evolution of black holes in the presence of vacuum energy. Using the assumption that Lambda remains constant with time, and a conjecture based on a paper by Mallett (1986), they reach the remarkable conclusion that black ho

Nahum Arav, Michael S. Brotherton, Robert H. Becker, Michael D. Gregg

We present detailed analyses of the absorption spectrum seen in QSO 2359-1241 (NVSS J235953-124148). Keck HIRES data reveal absorption from twenty transitions arising from: He I, Mg I, Mg II, Ca II, and Fe II. HST data show broad absorption lines (BALs) from Al III 1857, C IV 1549, Si IV 1397, and N V 1240. Absorption from excited Fe II states constrains the

M. S. Brotherton, Nahum Arav, R. H. Becker, Hien D. Tran

We report the discovery of a bright quasar (E=15.8, z=0.868) associated with the flat spectrum radio source NVSS J235953-124148. This quasar we designate QSO 2359-1241 possesses a rare combination of extreme properties that make it of special interest. These properties include: intrinsic high-velocity outflow seen in absorption for both high and low-ionizati

R. C. Nichol, C. A. Collins, S. L. Lumsden

We announce here the public availability of the Edinburgh/Durham Southern Galaxy Catalogue (EDSGC, http://www.edsgc.org). This objective galaxy catalogue was constructed using the COSMOS micro-densitometer at the Royal Observatory Edinburgh and constitutes one of the largest digitized galaxy surveys currently in existence. The EDSGC contains a total of 1,495

Vivek Aji, Nigel Goldenfeld

We show that hyperscaling and finite-size scaling imply that the probability distribution of the order parameter in finite size critical systems exhibit data collapse. We consider the examples of equilibrium critical systems, and a statistical model of ecology. We explain recent observations that the probability distribution of turbulent power fluctuations i

Benjamin D. Wandelt, Krzysztof M. Gorski

We propose fast, exact and efficient algorithms for the convolution of two arbitrary functions on the sphere which speed up computations by a factor \order{\sqrt{N}} compared to present methods where $N$ is the number of pixels. No simplifying assumptions are made other than bandlimitation. This reduces typical computation times for convolving the full sky w

Gideon Alexander, Edward Sarkisyan

Here we report on a study aimed to explore the dependence of the genuine multiparticle correlations on the number of sources while the influence of other possible factors affecting the multihadron production is avoided. The analysis utilised the normalised cumulants, calculated in three-dimensional phase space, of the reaction e+e- -> Z -> hadrons using a la

Antony A. Stark, John Bally, Simon P. Balm, T. M. Bania

AST/RO, a 1.7 m diameter telescope for astronomy and aeronomy studies at wavelengths between 200 and 2000 microns, was installed at the South Pole during the 1994-1995 Austral summer. The telescope operates continuously through the Austral winter, and is being used primarily for spectroscopic studies of neutral atomic carbon and carbon monoxide in the inters

Shyamoli Chaudhuri

Superseded and extended in hep-th/0105110 and hep-th/0208112.

V. M. Apalkov, T. Chakraborty

We report on our study of the luminescence spectra of a quantum cascade laser in the presence of an external magnetic field tilted from the direction perpendicular to the electron plane. The effect of the tilted field is to allow novel optical transitions because of the coupling of intersubband-cyclotron energies. We find that by tuning the applied field, on

T. Lofwander, V. S. Shumeiko, G. Wendin

We study spontaneous time-reversal symmetry breaking at Josephson tunnel junctions of d-wave superconductors in the absence of subdominant components of the order parameter. For tunnel junctions, when the orientation is close to 0/45 (for which a gap lobe points towards the junction on one side and a gap node on the other), the mechanism of the symmetry brea

A. J. Garcia-Adeva, D. L. Huber

A quantum mean field theory of the pyrochlore lattice is presented. The starting point is not the individual magnetic ions, as in the usual Curie-Weiss mean field theory, but a set of interacting corner sharing tetrahedra. We check the consistency of the model against magnetic susceptibility data, and find a good agreement between the theoretical predictions

A. Stoimenow

We prove a finiteness property of the values of the skein polynomial of homogeneous knots which allows to establish large classes of such knots to have arbitrarily unsharp Bennequin inequality (for the Thurston-Bennequin invariant of any of their Legendrian embeddings in the standard contact structure of R^3), and a give a short proof that there are only fin

V. Kokoouline, J. Vala, R. Kosloff

We develop two schemes for tuning the scattering length on the ground triplet state of Cs_2. First, an absolute value of the triplet scattering length of ^{133}Cs_2 is determined using the experimental data (Fioretti et al, Eur.Phys.J. 5, 389 (1999)). We demonstrate that the large scattering length can be made small and positive by coupling of the ^3Σ_u^+ (6

Chao-Shang Huang, Liao Wei, Qi-Shu Yan, Shou-Hua Zhu

The renormalization group equations(RGEs) of non-universal soft supersymmetric breaking terms with CP violating phases are analyzed in this paper. We obtain the analytic solutions of RGEs by directly solving the RGEs themselves. Compared with the method of spurion expansion our approach proves to be simple and succinct, and easy to extend to the case of comp

I. T. Drummond

We present a bi-metric theory of gravity containing a length scale of galactic size. For distances less than this scale the theory satisfies the standard tests of General Relativity. For distances greater than this scale the theory yields an effective gravitational constant much larger than the locally observed value of Newton&#39;s constant. The transition

Martin Tamm

In this paper, we use methods from differential geometry and statistical mechanics to investigate a model for the concept of mass. The theory is not quantum mechanical in the usual sense, although certain features like multiple histories and uncertainty are included in a natural way.

Yukito IBA

We give a cross-disciplinary survey on ``population&#39;&#39; Monte Carlo algorithms. In these algorithms, a set of ``walkers&#39;&#39; or ``particles&#39;&#39; is used as a representation of a high-dimensional vector. The computation is carried out by a random walk and split/deletion of these objects. The algorithms are developed in various fields in physic

F. Vernizzi, A. Melchiorri, R. Durrer

We present an alternative scenario for cosmic structure formation where initial fluctuations are due to Kalb-Ramond axions produced during a pre-big bang phase of inflation. We investigate whether this scenario, where the fluctuations are induced by seeds and therefore are of isocurvature nature, can be brought in agreement with present observations by a sui

S. A. Mikhailov

I present a new approach to the many-body ground state of quantum-Hall systems. The method describes the behavior of a two-dimensional electron system at all Landau-level filling factors $ν$, continuously as a function of magnetic field, and enables one to analytically calculate any physical value, characterizing the system, at all $ν$. New proposed trial ma

V. V. Anisovich, V. A. Nikonov, J. Nyiri

Rich experimental data accumulated in the past few years in the hadronic $Z^0$ decays allow one to check the quark combinatorics relations for a new type of processes, namely: quark jets in the decays $Z^0 \to q\bar q \to hadrons$. In this paper we review quark combinatorics rules for the yields of vector and pseudoscalar mesons, $V/P$, in the central and fr

O. G. Tchikilev

An explicit solution of non-critical time-homogeneous branching processes is described.

Sorina Lazanu, Ionel Lazanu

The concentration of primary radiation induced defects has been previously estimated considering both the explicit mechanisms of the primary interaction between the incoming particle and the nuclei of the semiconductor lattice, and the recoil energy partition between ionisation and displacements, in the frame of the Lindhard theory. The primary displacement

Zurab Kakushadze

We point out some subtleties with gauge fixings (which sometimes include the so-called ``brane bending&#39;&#39; effects) typically used to compute the graviton propagator on the Randall-Sundrum brane. In particular, the brane, which has non-vanishing tension, explicitly breaks some part of the diffeomorphisms, so that there are subtleties arising in going t

Anthony Challinor, Pablo Fosalba, Daniel Mortlock, Mark Ashdown

We discuss all-sky convolution of the instrument beam with the sky signal in polarimetry experiments, such as the Planck mission which will map the temperature anisotropy and polarization of the cosmic microwave background (CMB). To account properly for stray light (from e.g. the galaxy, sun, and planets) in the far side-lobes of such an experiment, it is ne

Xiao-Gang He, J. P. Ma, Chung-Yi Wu

We study $B\to ϕK$ and $B\to ϕX_s$ decays in the heavy quark limit using perturbative QCD. The next leading order corrections introduce substantial modifications to the naive factorization results (more than 50%). The branching ratio $Br(B\to ϕK)$ is predicted to be in the range $(F^{B\to K}_1(m^2_ϕ)/0.33)^2(3.5\sim 4.2) \times 10^{-6}$ which is within the o

Hitoshi Inamori

Modifications to a previous proof of the security of EPR-based quantum key distribution are proposed. This modified version applies to a protocol using three conjugate measurement bases rather than two. A higher tolerable error rate is obtained for the three-basis protocol.

V. B. Svetovoy, M. V. Lokhanin

We analyse the result of precise measurement of the Casimir force between bodies covered with gold. The values of the parameters used to extrapolate the gold dielectric function to low frequencies are very important and discussed in detail. The finite temperature effect is shown to exceed considerably the experimental errors. The upper limit on the force is

M. A. Nielsen

What fundamental constraints characterize the relationship between a mixture $ρ= \sum_i p_i ρ_i$ of quantum states, the states $ρ_i$ being mixed, and the probabilities $p_i$? What fundamental constraints characterize the relationship between prior and posterior states in a quantum measurement? In this paper we show that there are many surprisingly strong con

A. S. Parkins, E. Larsabal

We describe and analyse numerically schemes (i) for entangling orthogonal motional modes of one or a few harmonically-trapped atoms or ions, and (ii) for transferring the entanglement from one of these local modes to a distant trapped atom (or atoms) via a light-mediated quantum state transfer procedure proposed in previous work [A.S. Parkins and H.J. Kimble

G. Yu. Kryuchkyan, N. T. Muradyan

We propose novel types of parametric oscillators generating both three-photon and four-photon bright light which are accessible for an experiment. The devices are based on the cascaded down-conversion processes and consist of second-order media inserted in two-resonant mode cavity. Discussion of dissipation and quantum features of the system are performed by

Yong-Sheng Zhang, Chuan-Feng Li, Guang-Can Guo

A scheme of quantum authentication is presented. Two parties share Einstein-Podolsky-Rosen (EPR) pairs previously as the authentication key which servers as encoder and decoder. The authentication is accomplished with local controlled-NOT operations and unitary rotations. It is shown that our scheme is secure even in the presence of an eavesdropper who has c

P. Corredoura, C. Adolphsen

The proposed Next Linear Collider contains a large number of linac RF systems with new requirements for wideband klystron modulation and accurate RF vector detection. The system will be capable of automatically phasing each klystron and compensating for beam loading effects. Accelerator structure alignment is determined by detection of the beam induced dipol

L. J. Rybarcyk, J. D. Schneider, H. V. Smith, L. M. Young

Recently, the Low-Energy Demonstration Accelerator (LEDA) portion of the Accelerator Production of Tritium (APT) project reached its 100-mA, 8-hr CW beam operation milestone. LEDA consists of a 75-keV proton injector, 6.7-MeV, 350-MHz CW radio-frequency quadrupole (RFQ) with associated high-power and low-level rf systems, a short high-energy beam transport (

Paul T. Greninger, Henry J. Rodarte

The Coupled Cavity Drift Tube Linac (CCDTL) used in the Accelerator for the Production of Tritium (APT) is fully described elsewhere [1]. The modules are composed of several machined and brazed segments that must account for the accumulation of dimensional tolerances in the build up of the stack. In addition, space requirements dictate that power fed to the

Sergey S. Kurennoy

Electromagnetic modeling with MAFIA of the combined beam position-phase monitors (BPPMs) for the Spallation Neutron Source (SNS) linac has been performed. Time-domain 3-D simulations are used to compute the signal amplitudes and phases on the BPPM electrodes for a given processing frequency, 402.5 MHz or 805 MHz, as functions of the beam transverse position.

R. Soliday, S. Pasky, M. Borland

The Advanced Photon Source (APS) linear accelerator has two thermionic cathode rf guns and one photocathode rf gun. The thermionic guns are used primarily for APS operations while the photocathode gun is used as a free-electron laser (FEL) driver. With each gun requiring a different lattice and timing configuration, the need to change quickly between guns pu

R. Arad, K. Tsigutkin, Yu. V. Ralchenko, Y. Maron

Spectroscopic investigations of the properties of a plasma produced by a flashboard plasma source, commonly used in pulsed plasma experiments, are presented. The plasma is used to prefill a planar 0.4-ms-conduction time plasma opening switch (POS). A novel gas-doping technique and a secondary surface flashover plasma source are used to locally dope the plasm

P. Huelsmann, W. F. O. Mueller, H. Klein

The operation of a Free Electron Laser (FEL) in the ultraviolet or in the X-ray regime requires the acceleration of electron bunches with an rms length of 25 to 50 micro meters. The wakefields generated by these sub picosecond bunches extend into the frequency range well beyond the threshold for Cooper pair breakup (about 750 GHz) in superconducting niobium

J. Kuzminski, K. C. D. Chan, R. Gentzlinger, P. Maccioni

During 1999, four 700-MHz, medium-beta (b = 0.64), superconducting radio frequency (SCRF) cavities for a high-intensity proton linac project at Los Alamos National Laboratory (LANL) were manufactured by industry. The SCRF cavities were designed by a LANL team in Los Alamos, New Mexico, USA, and manufactured at a CERCA plant in Romans, France. The cavities we

W. T. Roybal, J. Bradley, D. Rees, P. A. Torrez

The high-power RF systems for the Accelerator Production of Tritium (APT) program require high-power circulators at 350 MHz and 700 MHz to protect 1 MW Continuous Wave (CW) klystrons from reflected power. The 350 MHz circulator is based on the CERN, ESRF, and APS designs and has performed very well. The 700 MHz circulator is a new design. Prototype 700 MHz c

W. Barth, P. Forck

The GSI Unilac was upgraded as a high current injector for the SIS in 1999. Therefore, the stripping section [1] at 1.4 MeV/u, where a beam transport under highest space charge conditions and multi beam operation had to be established, was completely new designed. Results of the commissioning of the stripper section will be presented. The beam transport to t

W. Barth

The disassembly of the Unilac prestripper linac of the Wideroe type took place at the beginning of 1999. An increase of more than two orders of magnitude in particle number for the most heavy elements in the SIS had to be gained. Since that time the new High Current Injector (HSI) consisting of H-type RFQ and DTL-structures for dual beam operation was instal

L. Dahl, P. Spaedtke

The UNILAC was improved for high current performance by replacing the Wideroe prestripper accelerator by an RFQ and an IH-type DTL. In addition, one of two ion source terminals was equipped with high current sources of MUCIS- and MEVVA-type. Therefore, a redesign of the LEBT from the ion source to the RFQ entrance was necessary. The new LEBT was installed at

H. Hayano

The wire scanners are used for a measurement of the very small beam size and the emittance in Accelerator Test Facility (ATF). They are installed in the extraction beam line of ATF damping ring. The extracted beam emittance are ex=1.3x10-9 m.rad, ey=1.7x10-11 m.rad with 2x109 electrons/bunch intensity and 1.3GeV energy. The wire scanners scan the beam by a t

P. L. Chapovsky, E. Ilisca

First theoretical analysis of the nuclear spin conversion in ethylene molecules (13^CCH4) has been performed. The conversion rate was found equal approx. 3x10^{-4} 1/s*Torr, which is in qualitative agreement with the recently obtained experimental value. It was shown that the ortho-para mixing in 13^CCH4 is dominated by the spin-rotation coupling. Mixing of

J. Alessi, D. Raparia, A. G. Ruggiero

This paper reports on the feasibility study of a proton Super-Conducting Linac (SCL) as a driver gor the High-Flux Breader Reactor (HFBR) at Brookhaven National Laboratory (BNL). The Linac operates in Continuos Wave (CW) mode to produce an average 10 MW of beam power. The Linac energy is 1.0 GeV. The average proton beam intensity is 10 mA.

D. Raparia, A. G. Ruggiero

This paper reports on the feasibility study of a proton Super-Conducting Linac (SCL) as a new injector to the Alternating Gradient Synchrotron (AGS) of the Brookhaven National Laboratory (BNL). The Linac beam energy is in the range of 1.5 to 2.4 GeV. The Beam intensity is adjusted to provide an average beam power of 4 MW at the top energy of 24 GeV. The repe

S. N. Dolya, W. I. Furman, V. V. Kobets, E. M. Laziev

&#34;LUE200&#34; - 200 MeV electron linac is being created at JINR as a driver of the pulsed neutron source &#34;IREN&#34; [1]. The special full-scale facilities for testing the main systems of LUE-200 (FSTF) are used at JINR, BINP, MEPhI and YerPhI [2]. The verification of the linac accelerating system is providing at the VEPP-5 preinjector constructed at B

M. Brunken, H. Genz, M. Gopych, H. -D. Graef

The S-DALINAC is a 130 MeV superconducting recirculating electron accelerator serving several nuclear and radiation physics experiments as well as driving an infrared free-electron laser. A system of normal conducting rf resonators for noninvasive beam position and current measurement was established. For the measurement of gamma-radiation inside the acceler

K. Colanero, M. -C. Chu

We study the exact classical solutions for a real scalar field inside a cavity with a wall whose motion is self-consistently determined by the pressure of the field itself. We find that, regardless of the system parameters, the long-time solution always becomes nonadiabatic and the field&#39;s energy concentrates into narrow peaks, which we explain by means

Xian-jian Zhou

In two models it is shown that a light pulse propagates from a vacuum into certain media with velocity greater than that of a light in a vacuum (c). By numerical calculation the propagating properties of such a light are given.

Yuri S. Kivshar, Elena A. Ostrovskaya

We study bit-parallel-wavelength (BPW) pulse transmission in multi-channel single-mode optical fiber links for high-performance computer networks. We develop a theory of the pulse shepherding effect earlier discovered in numerical simulations, and also describe the families of the BPW solitons and bifurcation cascades in a system of N coupled nonlinear Schrö

Akito Arima, Wolfgang Bentz, Toshio Suzuki, Toshio Suzuki

The recently obtained experimental result for the quenching of the GT sum rule in the reaction ^90Zr(p,n)^90Nb is used to extract the value of the Landau-Migdal parameter g_{NΔ}&#39;, taking into account also the effect of the finite range meson exchange interactions. The extracted value is compared to the one obtained in the π+ρexchange model by explicitly

R. L. Ray, R. S. Longacre

A fast, simple to use Monte Carlo based event generator is presented which is intended to facilitate simulation studies and the development of analysis software for the Solenoidal Tracker at RHIC (Relativistic Heavy Ion Collider) (STAR) experiment at the Brookhaven National Laboratory (BNL). This new event generator provides a fast, convenient means for prod

Victor Nistor

We define the equivariant family index of a family of elliptic operators invariant with respect to the free action of a bundle $\GR$ of Lie groups. If the fibers of $\GR \to B$ are simply-connected solvable, we then compute the Chern character of the (equivariant family) index, the result being given by an Atiyah-Singer type formula. We also study traces on

Victor Nistor

We give a detailed calculation of the Hochschild and cyclic homology of the algebra $\CIc(G)$ of locally constant, compactly supported functions on a reductive p-adic group G. We use these calculations to extend to arbitrary elements the definition the higher orbital integrals introduced in \cite{Blanc-Brylinski} for regular semisimple elements. Then we exte

Jeffrey C. Lagarias, Sandor Szabo

A spectral set in R^n is a set X of finite Lebesgue measure such that L^2(X) has an orthogonal basis of exponentials. It is conjectured that every spectral set tiles R^n by translations. A set of translations T has a universal spectrum if every set that that tiles by translations by T has this spectrum. A recent result proved that many periodic tiling sets h

Moulay-Tahar Benameur, Victor Nistor

We identify the periodic cyclic homology of the algebra of complete symbols on a differential groupoid $\GR$ in terms of the cohomology of $S^*(\GR)$, the cosphere bundle of $A(\GR)$, where $A(\GR)$ is the Lie algebroid of $\GR$. We also relate the Hochschild homology of this algebra with the homogeneous Poisson homology of the space $A^*(\GR) \smallsetminus

Robert Lauter, Victor Nistor

We use algebras of pseudodifferential operators on groupoids to study geometric operators on non-compact manifolds and singular spaces. The first step is to establish that the geometric operators are in our algebras. This then leads to criteria for Fredholmness for geometric operators on suitable non-compact manifolds, as well as to an inductive procedure to

Jennifer M. Johnson, János Kollár

We determine the complete list of anticanonically embedded quasi smooth log del Pezzo surfaces in weighted projective 3-spaces. We prove that many of these admit a Kähler-Einstein metric and most of them do not have tigers.

Silviu Olariu

Planar commutative n-complex numbers of the form u=x_0+h_1x_1+h_2x_2+...+h_{n-1}x_{n-1} are introduced in an even number n of dimensions, the variables x_0,...,x_{n-1} being real numbers. The planar n-complex numbers can be described by the modulus d, by the amplitude ρ, by n/2 azimuthal angles ϕ_k, and by n/2-1 planar angles ψ_{k-1}. The exponential functio

Silviu Olariu

Polar commutative n-complex numbers of the form u=x_0+h_1x_1+h_2x_2+...+h_{n-1}x_{n-1} are introduced in n dimensions, the variables x_0,...,x_{n-1} being real numbers. The polar n-complex number can be represented, in an even number of dimensions, by the modulus d, by the amplitude ρ, by 2 polar angles θ_+,θ_-, by n/2-2 planar angles ψ_{k-1}, and by n/2-1 a

Silviu Olariu

Two distinct systems of commutative complex numbers in 6 dimensions of the polar and planar types of the form u=x_0+h_1x_1+h_2x_2+h_3x_3+h_4x_4+h_5x_5 are described in this work, where the variables x_0, x_1, x_2, x_3, x_4, x_5 are real numbers. The polar 6-complex numbers introduced in this paper can be specified by the modulus d, the amplitude ρ, and the p

Silviu Olariu

A system of commutative complex numbers in 5 dimensions of the form u=x_0+h_1x_1+h_2x_2+h_3x_3+h_4x_4 is described in this paper, the variables x_0, x_1, x_2, x_3, x_4 being real numbers. The operations of addition and multiplication of the 5-complex numbers introduced in this work have a geometric interpretation based on the the modulus d, the amplitude ρ,

Silviu Olariu

Commutative complex numbers of the form u=x+αy+βz+γt in 4 dimensions are studied, the variables x, y, z and t being real numbers. Four distinct types of multiplication rules for the complex bases α, βand γare investigated, which correspond to hypercomplex entities called in this paper circular fourcomplex numbers, hyperbolic fourcomplex numbers, planar fourc

Silviu Olariu

A system of commutative hypercomplex numbers of the form w=x+hy+kz are introduced in 3 dimensions, the variables x, y and z being real numbers. The multiplication rules for the complex units h, k are h^2=k, k^2=h, hk=1. The operations of addition and multiplication of the tricomplex numbers introduced in this paper have a simple geometric interpretation base

Silviu Olariu

A system of commutative hyperbolic complex numbers in 2 dimensions is studied in this paper. Exponential and trigonometric forms are obtained for these hyperbolic twocomplex numbers. Expressions are given for the elementary functions of hyperbolic twocomplex variable. The functions of a hyperbolic twocomplex variable which are defined by power series are ana

J. Scott Carter, Seiichi Kamada, Masahico Saito

We introduce an equivalence relation, called stable equivalence, on knot diagrams and closed curves on surfaces. We give bijections between the set of abstract knots, the set of virtual knots, and the set of the stable equivalence classes of knot diagrams on surfaces. Using these bijections, we define concordance and link homology for virtual links. As an ap

Tom H. Koornwinder

A systematic exposition is given of the theory of invariant differential operators on a not necessarily reductive homogeneous space. This exposition is modelled on Helgason&#39;s treatment of the general reductive case and the special non-reductive case of the space of horocycles. As a final application the differential operators on (not a priori reductive)

Inhyeop Yi

We compute the K-groups of C^*-algebras arising from one-dimensional generalized solenoids. The results show that Ruelle algebras from one-dimensional generalized solenoids are one-dimensional generalizations of Cuntz-Krieger algebras.

S. Nojiri, O. Obregon, S. D. Odintsov, S. Ogushi

We report our recent results concerning d5 gauged supergravity (dilatonic gravity) considered on AdS background. The finite action on such background as well as d4 holographic conformal anomaly (via AdS/CFT correspondence) are found. In such formalism the bulk potential is kept to be arbitrary, dilaton dependent function. Holographic RG in such theory is bri

A. Yu. Segal

The model of point particle in general external fields is considered and the generalized equivalence principle is suggested identifying all backgrounds which give rise to equivalent particle dynamics. The equivalence transformations for external fields are interpreted as gauge ones. The gauge group appears to be a semidirect product of all phase space canoni

Alejandro Ayala

Working within the linear sigma model at finite temperature, we construct effective one-loop vertices and propagators satisfying the chiral Ward identities, for small pion momentum and mass compared to the sigma mass. We obtain an expansion for the pion dispersion relation up to second order in the parameter m_pi^2/4pi^2f_pi^2. At leading order, this expansi

M. R. Ahmady, F. A. Chishtie, V. Elias, T. G. Steele

Utilizing asymptotic Pade-approximant methods, we estimate the three-loop order MS-bar coefficients of alpha_s^3[\log(μ^2/m^2_b(μ)]^k terms [k = {0,1,2,3}] within the $b \to u\ell^-\barν_\ell$ decay rate. Except for the coefficient of the k = 0 term, all other coefficients may also be obtained via renormalization-group (RG) methods. The relative errors in as

F. A. Chishtie, V. Elias, T. G. Steele

Using asymptotic Pade approximant methods, we have calculated the O(alpha_s^5) contribution to the Standard-Model H to gg decay rate. This process is of particular interest because of the slow convergence evident from the known terms of its QCD series. The O(alpha_s^5) term is expressed as a 3rd degree polynomial in $L= log (\frac{μ^2}{m_t^2(μ)})$. We find t

M. Raidal

If the Standard Model is embedded in a left-right symmetric gauge theory at the TeV scale, the pair production of light W-bosons in e^+e^- collisions, e^+e^- -> W^+W^-, will be affected by mixings in the gauge and neutrino sectors, and by the t-channel exchange of a heavy right-handed neutrino. The modification of the cross section by these new effects is st

A. I. Davydychev, P. Osland, L. Saks

One-loop off-shell contributions to the quark-gluon vertex are calculated, in an arbitrary covariant gauge and in arbitrary space-time dimension, including quark-mass effects. It is shown how one can get results for all on-shell limits of interest directly from the off-shell expressions. In order to demonstrate that the Ward-Slavnov-Taylor identity for the q

G. J. Gounaris

The Standard Model contributions to the processes $γγ\to γγ$, $γZ$ and ZZ at sufficiently high energies, are found to be helicity conserving and almost purely imaginary. This is due to the W-loop contribution, which is much bigger than the fermionic ones at such energies. Thus the structure of these amplitudes acquires an impressive simplicity at high energi

T. Barnes

This short contribution is a {\it lite} MESON2000 conference summary. As appropriate for the 600th anniversary of the Jagellonian University, it begins with a brief summary of the last 600 years of European history and its place in hadron physics. Next a ``physicist chirality&#39;&#39; order parameter PC is introduced. When applied to MESON2000 plenary speak

N. Kivel, L. Mankiewicz

We applied QCD Light Cone Sum Rules to estimate power corrections to the helicity-conserving amplitude in the process $γ^*γ\to ππ$. We found that above $Q^2 \sim 4$ GeV$^2$ power corrections are numerically small and the twist-2 part dominates.The amplitude can be reliably calculated in this region using models of $2 π$ distribution amplitudes as an input. W

C. Bloechinger, F. Franke, H. Fraas

We study the associated production of selectrons and neutralinos with subsequent leptonic decay of the selectron in eγscattering within the framework of MSSM and NMSSM. Due to the weak couplings of singlino dominated neutralinos, associated neutralino production e^+ + e^- -> neutralino_1 + neutralino_2 at a linear collider can be strongly suppressed in some

Debrupa Chakraverty, Debajyoti Choudhury

We investigate the possible role that baryon number violating Yukawa interactions may take in the inclusive decay $ B \to X_s γ$. The constraints, derived using the experimental results of the CLEO collaboration, turn out, in many cases, to be more stringent than the existing bounds.

Wojciech Krolikowski

The alternative formulated in the title has a chance to be settled, when the existence of the LSND effect is experimentally excluded or confirmed. The first option, much discussed in literature, works in the case of three active neutrinos $ν_e, ν_μ, ν_τ$, when among their massive states $ν_1, ν_2, ν_3$ there is no direct mixing between $ν_1$ and $ν_3$, and t

J. Nemchik

We present the first evaluation of the color dipole diffraction slope from the data on diffractive photo- and electroproduction of vector mesons. The energy and dipole size dependence of the found dipole diffraction slope are consistent with the color dipole gBFKL dynamics.

C. Balazs

Resummed QCD corrections to the transverse momentum ($Q_T$) distribution of the Standard Model Higgs boson, produced at the CERN Large Hadron Collider, are presented. The small $Q_T$ factorization formalism is reviewed, which is used to extend the standard hadronic factorization theorem to the low $Q_T$ region, with emphasis on the matching to the standard h

Y. Bylinsky, A. M. Lombardi, W. Pirkl

The RFQD is designed to decelerate antiprotons of momentum 100 MeV/c (kinetic energy 5.33MeV)down to a kinetic energy variable between ~10 keV and 120 keV. Inside the RFQ body, at ground potential, the rf structure of the four-rod type is mounted on insulating supports. It can be biased between plus/minus 60 kV dc to achieve the continuous adjustment of outp

E791 Collaboration

We present a measurement of asymmetries in the production of $Λ_c^+$ and $Λ_c^-$ baryons in 500 GeV/c $π^-$--nucleon interactions from the E791 experiment at Fermilab. The asymmetries were measured as functions of Feynman x ($x_F$) and transverse momentum squared ($p_T^2$) using a sample of $1819 \pm 62$ $Λ_c$&#39;s observed in the decay channel $Λ_c \to pK^

Danilo Babusci, Massimo Giovannini

The sensitivity of a pair of VIRGO interferometers to gravitational waves backgrounds (GW) of cosmological origin is analyzed for the cases of maximal and minimal overlap of the two detectors. The improvements in the detectability prospects of scale-invariant and non-scale-invariant logarithmic energy spectra of relic GW are discussed.

Carroll O. Alley, Huseyin Yilmaz

E. D. Fackerell claims: 1) that Alley and Yilmaz treatment of parallel slabs in general relativity is wrong because the Yilmaz metric used is not a solution of the field equations of general relativity; 2) he also claims that the correct treatment of the parallel slab problem in general relativity must be based on the so-called Taub metric. We show below tha

Uri Zwick

We present two new algorithms for solving the {\em All Pairs Shortest Paths} (APSP) problem for weighted directed graphs. Both algorithms use fast matrix multiplication algorithms. The first algorithm solves the APSP problem for weighted directed graphs in which the edge weights are integers of small absolute value in $\Ot(n^{2+μ})$ time, where $μ$ satisfies