January 2002 arXiv papers — page 17

A. Guarino, S. Ciliberto, A. Garcimartin, M. Zei

The acoustic emission of fracture precursors, and the failure time of samples of heterogeneous materials (wood, fiberglass) are studied as a function of the load features and geometry. It is shown that in these materials the failure time is predicted with a good accuracy by a model of microcrack nucleation proposed by Pomeau. We find that the time interval $

Arnaud Buhot, Mirta B. Gordon, Jean-Pierre Nadal

We show that the lower bound to the critical fraction of data needed to infer (learn) the orientation of the anisotropy axis of a probability distribution, determined by Herschkowitz and Opper [Phys.Rev.Lett. 86, 2174 (2001)], is not always valid. If there is some structure in the data along the anisotropy axis, their analysis is incorrect, and learning is p

Pierpaolo Bruscolini, Lapo Casetti

The hydrophobic effect is the dominant force which drives a protein towards its native state, but its physics has not been thoroughly understood yet. We introduce an exactly solvable model of the solvation of non-polar molecules in water, which shows that the reduced number of allowed configurations of water molecules when the solute is present is enough to

Pierpaolo Bruscolini, Lapo Casetti

We introduce an exactly solvable statistical-mechanical model of the hydration of non-polar compounds, based on grouping water molecules in clusters where hydrogen bonds and isotropic interactions occur; interactions between clusters are neglected. Analytical results show that an effective strengthening of hydrogen bonds in the presence of the solute, togeth

H. He, P. Bourges, Y. Sidis, C. Ulrich

An unusual spin excitation mode observed by neutron scattering has inspired numerous theoretical studies of the interplay between charged quasiparticles and collective spin excitations in the copper oxide high temperature superconductors. The mode has thus far only been observed in materials with crystal structures consisting of copper oxide bilayers, and it

I. Janecek, P. Vasek

Hall effect below Tc in multiphase superconductors has been studied on Bi-based superconductors. Samples with different relative content of 2212 and 2223 phase have been prepared. The phase content has been verified by X-ray diffraction. Results show that while resistance and ac susceptibility is almost insensitive to the content of 2212 phase, the qualitati

N. Kikuchi, A. Gent, J. M. Yeomans

We investigate numerically the dynamical behaviour of a polymer chain collapsing in a dilute solution. The rate of collapse is measured with and without the presence of hydrodynamic interactions. We find that hydrodynamic interactions both accelerate polymer collapse and alter the folding pathway.

E. Gorecka, D. Pociecha, M. Cepic, B. Zeks

The phase diagram of the prototype antiferroelectric liquid crystal MHPOBC in dependence of enantiomeric excess was measured. It was shown that the SmCbeta phase in very pure samples is the SmCFI2 phase with a four layer structure, and only after small racemization it transforms into the ferroelectric SmC phase. The phase diagram was theoretically explained

Atsushi Goto, W. G. Clark, Patrik Vonlanthen, Kenji B. Tanaka

We report measurements of the anisotropy of the spin echo decay for the inner layer Cu site of the triple layer cuprate, Hg_0.8Re_0.2Ba_2Ca_2Cu_3O_8 (T_c=126 K) in the pseudogap T regime below T_pg ~ 170 K and the corresponding analysis for their interpretation. As the field alignment is varied, the shape of the decay curve changes from Gaussian (H_0 \parall

D. E. Feldman

In this review we consider glass states of several disordered systems: vortices in impure superconductors, amorphous magnets, and nematic liquid crystals in random porous media. All these systems can be described by the random-field or random-anisotropy O(N) model. Even arbitrarily weak disorder destroys long range order in the O(N) model. We demonstrate tha

W. A. Hofer, A. J. Fisher

We propose a method to determine the direction of surface magnetization and local magnetic moments on the atomic scale. The method comprises high resolution scanning tunneling microscope experiments in conjunction with first principles simulations of the tunneling current. The potential of the method is demonstrated on a model system, antiferromagnetic Mn ov

Maia Angelova

Lie-algebraic and quantum-algebraic techniques are used in the analysis of thermodynamic properties of molecules and solids. The local anharmonic effects are described by a Morse-like potential associated with the $su(2)$ algebra. A vibrational high-temperature partition function and the related thermodynamic potentials are derived in terms of the parameters

J. Gonzalez

We propose the model of a manifold of one-dimensional interacting electron systems to account for the superconductivity observed in ropes of nanotubes. We rely on the strong suppression of single-particle hopping between neighboring nanotubes in a disordered rope and conclude that the tunnelling takes place in pairs of electrons, which are formed within each

Helen R. Eisenberg Daniel Kandel

We showed that a wetting layer in epitaxially strained thin films which decreases with increasing lattice mismatch strain arises due to the variation of nonlinear elastic free energy with film thickness. We calculated how and at what thickness a flat film becomes unstable to perturbations of varying size for films with both isotropic and anisotropic surface

L. C. Malacarne, R. S. Mendes, E. K. Lenzi

In the nonextensive Tsallis scenario, Page's conjecture for the average entropy of a subsystem[Phys. Rev. Lett. {\bf 71}, 1291(1993)] as well as its demonstration are generalized, i.e., when a pure quantum system, whose Hilbert space dimension is $mn$, is considered, the average Tsallis entropy of an $m$-dimensional subsystem is obtained. This demonstrat

J. Froehlich, B. Pedrini

We discuss the ordinary quantum Hall effect and a higher-dimensional cousin. We consider the dimensional reduction of these effects to 1+1 and 3+1 space-time dimensions, respectively. After dimensional reduction, an axion field appears, which plays the role of a space-time dependent difference of chemical potentials of chiral modes. As applications, we sketc

D. H. E. Gross

A geometric foundation thermo-statistics is presented with the only axiomatic assumption of Boltzmann's principle S(E,N,V)=k\ln W. This relates the entropy to the geometric area e^{S(E,N,V)/k} of the manifold of constant energy in the finite-N-body phase space. From the principle, all thermodynamics and especially all phenomena of phase transitions and c

A. Gurevich, M. S. Rzchowski, G. Daniels, S. Patnaik

We show that low-angle grain boundaries (GB) in high-temperature superconductors exhibit intermediate Abrikosov vortices with Josephson cores, whose length $l$ along GB is smaller that the London penetration depth, but larger than the coherence length. We found an exact solution for a periodic vortex structure moving along GB in a magnetic field $H$ and calc

S. L. Narasimhan, P. S. R. Krishna, M. Ramanadham, K. P. N. Murthy

The Interacting Growth Walk (IGW) is a kinetic algorithm proposed recently for generating long, compact, self avoiding walks. The growth process in IGW is tuned by the so called growth temperature $T' = 1/(k_B β')$. On a square lattice and at $T' = 0$, IGW is attrition free and hence grows indefinitely. In this paper we consider IGW on a honeycom

Keshav N. Shrivastava

The fractions of constant conductivity, i, where the conductivity is ie^2/h are interpretted to arise from the summation of two frequencies, ω_1+ ω_2, type of processes so that the quantum Hall effect becomes a problem of spectroscopic energy levels. We describe the conversion of resistivity to the frequency spectrum. An effort is made to look at the recent

Alessandro Torcini, Paolo Politi

Surface growth models may give rise to unstable growth with mound formation whose tipical linear size L increases in time. In one dimensional systems coarsening is generally driven by an attractive interaction between domain walls or kinks. This picture applies to growth models for which the largest surface slope remains constant in time (model B): coarsenin

Ramesh Narayan

Nearby galactic nuclei are observed to be very much dimmer than active galactic nuclei in distant galaxies. The Chandra X-ray Observatory has provided a definitive explanation for why this is so. With its excellent angular resolution, Chandra has imaged hot X-ray-emitting gas close to the gravitational capture radius of a handful of supermassive black holes,

D. Bersier

I present photometric and radial velocity data for Galactic Cepheids, most of them being in the southern hemisphere. There are 1250 Geneva 7-color photometric measurements for 62 Cepheids, the average uncertainty per measurement is better than 0.01 mag. A total of 832 velocity measurements have been obtained with the CORAVEL radial velocity spectrograph for

C. R. Cowley, F. Castelli

We compare the results of Balmer-line calculations using recent theory and improved computational algorithms with those from the widely-used SYNTHE and BALMER9 routines. The resulting profiles are mostly indistinguishable. Good fits to the normalized solar Balmer lines H$α$ through H$δ$ are obtained (apart from the cores) using the recent unified-broadening

Angela V. Olinto

Contrary to earlier expectations, several cosmic ray events with energies above $10^{20}$ eV have been reported by a number of ultra-high energy cosmic ray observatories. According to the AGASA experiment, the flux of such events is well above the predicted Greisen-Zatsepin-Kuzmin cutoff due to the pion production of extragalactic cosmic ray protons off the

J. S. B. Wyithe, R. E. Wilson

Published measurements of distances to detached eclipsing binaries in the Large Magellanic Cloud combine stellar surface areas (in absolute units) determined from photometric light and radial velocity curves with surface brightnesses from model atmospheres and observed spectra. The method does not require the stars to be normal or undistorted, and is not lim

M. Ribo, J. M. Paredes, G. E. Romero, P. Benaglia

We have compiled optical and radio astrometric data of the microquasar LS 5039 and derived its proper motion. This, together with the distance and radial velocity of the system, allows us to state that this source is escaping from its own regional standard of rest, with a total systemic velocity of about 150 km/s and a component perpendicular to the galactic

P. Barmby, S. Holland, J. P. Huchra

We analyze the structural parameters of the largest-available sample of spatially resolved extragalactic globular clusters. The images of M31 GCs were found in a search of HST archival data, described in a companion paper. We measure the ellipticities and position angles of the clusters and conclude that the ellipticities are consistent with being caused by

Jodie Martin, Kiriaki Xilouris, Noam Soker

We report the detection of an Halpha emission-line structure in the upstream side of the planetary nebula NGC 40, which is predicted by numerical simulations, and which is attributed to Rayleigh-Taylor instability. Such a Rayleigh-Taylor instability is expected to occur at early stages of the interaction process between the interstellar medium (ISM) and a fa

Giovanni Carraro

We present CCD UBVI observations obtained in the field of the two previously unstudied dissolving open cluster candidates NGC 7036 and NGC 7772. Our analysis suggests that both the objects are Open Cluster Remnants (OCR). NGC 7036 is an open cluster remnant with a core radius of about 3-4 arcmin. We derive for the first time estimates of its fundamental para

Joshua E. Barnes

Observations indicate that much of the interstellar gas in merging galaxies may settle into extended gaseous disks. Here, I present simulations of disk formation in mergers of gas-rich galaxies. Up to half of the total gas settles into embedded disks; the most massive instances result from encounters in which both galaxies are inclined to the orbital plane.

V. de Heij, R. Braun, W. B. Burton

We describe an automated search through the Leiden/Dwingeloo HI Survey (LDS) for high-velocity clouds north of Dec=-28 deg. From the general catalog we extract a sample of isolated high-velocity clouds, CHVCs: anomalous-velocity HI clouds which are sharply bounded in angular extent with no kinematic or spatial connection to other HI features down to a limiti

Nicola Masetti

In October 1997, the Italian and Dutch GRB teams started a collaboration on ESO optical follow-up of rapidly and accurately localized GRBs. Subsequently, starting April 1, 2000, this collaboration was extended to astronomers from other countries, who contributed their expertise for the creation of a Consortium committed to the study of GRB counterparts and h

N. V. Boris, C. J. Donzelli, M. G. Pastoriza, A. Rodriguez-Ardila

We present BVI photometry of ten Seyfert 1 galaxies and narrow band H-alpha images for six of these objects as well. The results indicate that the luminosity sample distribution has an amplitude of almost 4 magnitudes with an average of M_B=-20.7. The observed morphologies are confined to early type galaxies. A barred structure is found in only 2 objects. De

Yves A. Gallant

I review the current status of Fermi acceleration theory at relativistic shocks. I first discuss the relativistic shock jump conditions, then describe the non-relativistic Fermi mechanism and the differences introduced by relativistic flows. I present numerical calculations of the accelerated particle spectrum, and examine the maximum energy attainable by th

Kyoko Matsushita, Elena Belsole, Alexis Finoguenov, Hans Böhringer

We report the results of a detailed analysis of the temperature structure of the X-ray emitting plasma halo of M~87, the cD galaxy of the Virgo Cluster. Using the MEKAL model, the data provide strong indications that the intracluster medium has a single phase structure locally, except the regions associated to the radio structures. The deprojected spectrum a

P. Veron, A. C. Goncalves, M. -P. Veron-Cetty

A few Seyfert 1s have a Hb profile with a red wing usually called the "red shelf". The most popular interpretation of this feature is that it is due to broad redshifted lines of Hb and [OIII]4959,5007; we have observed two Seyfert 1s displaying a "red shelf" and showed that in these two objects the main contributor is most probably the HeI 49

J. D. M. Dewi, O. R. Pols, G. J. Savonije, E. P. J. van den Heuvel

The evolution of helium stars with masses of 1.5 - 6.7 M_sun in binary systems with a 1.4 M_sun neutron-star companion is presented. Such systems are assumed to be the remnants of Be/X-ray binaries with B-star masses in the range of 8 - 20 M_sun which underwent a case B or case C mass transfer and survived the common-envelope and spiral-in process. The orbit

J. Halenka, J. Madej, K. Langer, A. Mamok

We present extensive tables of the atomic partition function (APF) for nickel ions, Ni I - Ni X. Partition functions are given over wide range of temperature, 10^3 K < T < 10^6 K, and lowering of ionization energy (0.001 eV < LIE < 5.0 eV), both taken as independent variables. Our APF take into account all energy levels predicted by quantum mechanics, includ

Alessandro Melchiorri

Recent measurements of the Cosmic Microwave Background Anisotropy have provided evidence for the presence of oscillations in the angular power spectrum. These oscillations are a wonderful confirmation of the standard cosmological scenario and allow us to derive constraints on many cosmological, astrophysical and inflationary parameters. If the discovery is c

Graham P. Smith

We are conducting a systematic lensing survey of X-ray luminous galaxy clusters at z~0.2 using the Hubble Space Telescope and large ground-based telescopes. We summarize initial results from our survey, including a measurement of the inner slope of the mass profile of A383, and a search for gravitationally lensed Extremely Red Objects.

L. N. Makarova, I. D. Karachentsev, E. K. Grebel, O. Yu. Barsunova

We present CCD surface photometry of 16 nearby dwarf galaxies, many of which were only recently discovered. Our sample comprises both isolated galaxies and galaxies that are members of nearby galaxy groups. The observations were obtained in the Johnson B and V bands (and in some cases in Kron-Cousins I). We derive surface brightness profiles, total magnitude

T. Kato

The origin of early superhumps, which are double-wave periodic modulations seen only during the earliest stage of WZ Sge-type outburst, has not been well understood. Based on recent discovery of two-armed arch-like patterns on Doppler tomograms in conjunction with early superhumps, we propose a new interpretation on the origin of early superhumps, following

Henry G. Roe, Imke de Pater, Bruce A. Macintosh, Seran G. Gibbard

Using adaptive optics on the W.M. Keck II telescope we imaged Titan several times during 1999 to 2001 in narrowband near-infrared filters selected to probe Titan&#39;s stratosphere and upper troposphere. We observed a bright feature around the south pole, possibly a collar of haze or clouds. Further, we find that solar phase angle explains most of the observ

Q. Daniel Wang

We present a ROSAT and ASCA study of the Einstein source X-9 and its relation to a shock-heated shell-like optical nebula in a tidal arm of the M81 group of interacting galaxies. Our ASCA observation of the source shows a flat and featureless X-ray spectrum well described by a multi-color disk blackbody model. The source most likely represents an optically t

Christopher O&#39;Dell

The Cosmic Microwave Background Radiation (CMB) is an invaluable probe of the conditions of the early universe. Recent measurements of its spatial anisotropy have allowed accurate determinations of several fundamental cosmological parameters, such as the curvature of the universe, the shape of the spectrum of primordial density fluctuations, and the contribu

Keith Horne, Bradley M. Peterson, Stefan J. Collier, Hagai Netzer

We present a series of simulations to demonstrate that high-fidelity velocity-delay maps of the emission-line regions in active galactic nuclei can be obtained from time-resolved spectrophotometric data sets like those that will arise from the proposed Kronos satellite. While previous reverberation-mapping experiments have established the size scale R of the

Martin Schnabl

The wedge states form an important subalgebra in the string field theory. We review and further investigate their various properties. We find in particular a novel expression for the wedge states, which allows to understand their star products purely algebraically. The method allows also for treating the matter and ghost sectors separately. It turns out, tha

David Berenstein

One can geometrically engineer supersymmetric field theories theories by placing D-branes at or near singularities. The opposite process is described, where one can reconstruct the singularities from quiver theories. The description is in terms of a noncommutative quiver algebra which is constructed from the quiver diagram and the superpotential. The center

Mauricio Cataldo

The fundamental metrics, which describe any static three-dimensional Einstein-Maxwell spacetime (depending only on a unique spacelike coordinate), are found. In this case there are only three independent components of the electromagnetic field: two for the vector electric field and one for the scalar magnetic field. It is shown that we can not have any super

Weiping Li, Peter Vermeire

This has been withdrawn by the authors.

A. J. M. Medved

Various studies have explored the possibility of explaining the Bekenstein-Hawking (black hole) entropy by way of some suitable state-counting procedure. Notably, many of these treatments have used the well-known Cardy formula as an intermediate step. Our current interest is a recent calculation in which Carlip has deduced the leading-order quantum correctio

V. A. Rodin, M. H. Urin

A semimicroscopical approach is applied to describe photoabsorption and partial photonucleon reactions accompanied by the excitation of the giant dipole resonance (GDR). The approach is based on the continuum-RPA (CRPA) with a phenomenological description for the spreading effect. The phenomenological isoscalar part of the nuclear mean field, momentum-indepe

M. Marcelli, M. C. Nucci

We show how the Lie group analysis method can be used in order to obtain first integrals of any system of ordinary differential equations. The method of reduction/increase of order developed by Nucci (J. Math. Phys. 37, 1772-1775 (1996)) is essential. Noether&#39;s theorem is neither necessary nor considered. The most striking example we present is the relat

Timothy J. Hollowood

We describe a new technique for calculating instanton effects in supersymmetric gauge theories applicable on the Higgs or Coulomb branches. In these situations the instantons are constrained and a potential is generated on the instanton moduli space. Due to existence of a nilpotent fermionic symmetry the resulting integral over the instanton moduli space loc

Matthias Blau, Jose Figueroa-O&#39;Farrill, Christopher Hull, George Papadopoulos

We show that the maximally supersymmetric pp-waves of IIB superstring and M-theories can be obtained as a Penrose limit of the supersymmetric AdS x S solutions. In addition we find that in a certain large tension limit, the geometry seen by a brane probe in an AdS x S background is either Minkowski space or a maximally supersymmetric pp-wave.

Joseph D Masters

We show that if M is a surface bundle over S^1 with fiber of genus 2, then for any integer n, M has a finite cover tilde(M) with b_1(tilde(M)) > n. A corollary is that M can be geometrized using only the `non-fiber&#39; case of Thurston&#39;s Geometrization Theorem for Haken manifolds.

E. Cappelluti, S. Ciuchi

We investigate the interplay between the formation of lattice and magnetic polaron in the case of a single hole in the antiferromagnetic background. We present an exact analytical solution of the Holstein-t-J model in infinite dimensions. Ground state energy, electron-lattice correlation function, spin bag dimension as well as spectral properties are calcula

Ulrich Bunke, Paul Turner, Simon Willerton

For smooth finite dimensional manifolds, we characterise gerbes with connection as functors on a certain surface cobordism category. This allows us to relate gerbes with connection to Turaev&#39;s 1+1-dimensional homotopy quantum field theories, and we show that flat gerbes are related to a specific class of rank one homotopy quantum field theories.

Oleg Lebedev

Torsion appears due to fermions coupled to gravity and leads to the strongest particle physics bounds on flat extra dimensions. In this work, we consider torsion constraints in the case of a warped extra dimension with brane and bulk fermions. From current data we obtain a 3-sigma bound on the TeV--brane mass scale scale Λ_π> 2.2 (10) TeV for the AdS curvatu

S. M. Rucinski

Methods used in the radial-velocity program of short-period binary systems at the David Dunlap Observatory are described with particular stress on the Broadening Function (BF) formalism. This formalism has permitted determination of radial velocities from complex spectra of multiple-component systems with component stars showing very different degree of rota

S. M. Rucinski, W. Lu, C. Capobianco, S. W. Mochnacki

Radial-velocity measurements and sine-curve fits to the orbital velocity variations are presented for the sixth set of ten close binary systems: SV Cam, EE Cet, KR Com, V410 Cyg, GM Dra, V972 Her, ET Leo, FS Leo, V2388 Oph, II UMa. All systems except FS Leo are double-lined spectroscopic binaries. The type of FS Leo is unknown while SV Cam is a close, detach

Chao-Shang Huang, Wei Liao

We show that with a good fit to the muon $g-2$ constraint, the CP asymmetry can be as large as 25% (15%) for $B^0_d \to τ^+ τ^-$ ($B^0_d \to μ^+ μ^-$) in SUGRA models with nonuniversal gaugino masses and MSSM. If tau events indentified at B factories the CP asymmetry in $B^0_d \to τ^+τ^-$ can be a powerful probe on physics beyond SM. An interesting case is t

A. G. Doroshkevich, P. D. Naselsky

In this paper we discuss the possible distortions of the ionization history of the universe caused by an injection of non-thermal energy due to decays of hypothetical Super Heavy Dark Matter (SHDM) particles. These particles are usually considered as a possible source of Ultra High Energy Cosmic Rays (UHECRs) in the framework of the Top-Down model. Estimates

Alice Sinatra, Carlos Lobo, Yvan Castin

We study the truncated Wigner method (TWM) applied to a weakly interacting Bose condensed gas perturbed away from thermal equilibrium. The idea of the method is to generate an ensemble of classical fields which samples the Wigner function of the initial thermal density operator, and to evolve each field with the Gross-Pitaevskii equation (GPE). In the first

Mitsuru Hamada

The highest fidelity of quantum error-correcting codes of length n and rate R is proven to be lower bounded by 1 - exp [-n E(R)+ o(n)] for some function E(R) on noisy quantum channels that are subject to not necessarily independent errors. The E(R) is positive below some threshold R&#39;, which implies R&#39; is a lower bound on the quantum capacity. This wo

Michael Murray

The first measurement of kaon phase space densities are presented as a function of transverse mass, center of mass energy and the number of participants. The kaon phase space density increases with the number of participants from e+e- to Pb+Pb collisions. However the ratio of the kaon and pion phase space densities at low transverse momentum is independent o

Daniel Collins, Nicolas Gisin, Sandu Popescu, David Roberts

We analyze the structure of correlations among more than two quantum systems. We introduce a classification of correlations based on the concept of non-separability, which is different {\em a priori} from the concept of entanglement. Generalizing a result of Svetlichny [Phys. Rev. D {\bf 35} (1987) 3066] on 3-particle correlations, we find an inequality for

J. Fjelstad, J. Fuchs, S. Hwang, A. M. Semikhatov

We construct logarithmic conformal field theories starting from an ordinary conformal field theory -- with a chiral algebra C and the corresponding space of states V -- via a two-step construction: i) deforming the chiral algebra representation on V\tensor End K[[z,1/z]], where K is an auxiliary finite-dimensional vector space, and ii) extending C by operato

Shardha Jogee, Johan H. Knapen, Seppo Laine, Isaac Shlosman

For decades, the grand-design SAB spiral galaxy NGC 5248 has been postulated to host a short bar of semi-major axis 22&#34; (1.6 kpc). From dynamical and morphological arguments, we argue, however, that its spiral structure is being driven by a large-scale bar whose corotation radius lies at around 115&#34; (8.6 kpc).Our estimate is based partially on a deep

Morihiko Saito

Let X be a smooth quasi-projective variety over the algebraic closure of the rational number field. We show that the cycle map of the higher Chow group to Deligne cohomology is injective and the higher Hodge cycles are generated by the image of the cycle map as conjectured by Beilinson and Jannsen, if the cycle map to Deligne cohomology is injective and the

Nicolas Couchoud

We study branes and orientifolds on the group manifold of SO(3). We consider particularly the case of the equatorial branes, which are projective planes. We show that a Dirac-Born-Infeld action can be defined on them, although they are not orientable. We find that there are two orientifold projections with the same spacetime action, which differ by their act

Makoto Takahashi, Takami Tohyama, Sadamichi Maekawa

We study the third-order nonlinear optical susceptibility $χ^{(3)}$ and photoexcited states of two-dimensional (2D) Mott insulators by using an effective model in the strong-coupling limit of a half-filled Hubbard model. In the numerically exact diagonalization calculations on finite-size clusters, we find that the coupling of charge and spin degrees of free

W. -Y. Hwang, X. -B. Wang, K. Matsumoto, J. Kim

We give a Shor-Preskill type security-proof to the quantum key distribution without public announcement of bases [W.Y. Hwang et al., Phys. Lett. A 244, 489 (1998)]. First, we modify the Lo-Chau protocol once more so that it finally reduces to the quantum key distribution without public announcement of bases. Then we show how we can estimate the error rate in

J. M. Marcaide, M. A. Perez-Torres, E. Ros, A. Alberdi

We observed SN1979C in M100 on 4 June 1999, about twenty years after explosion, with a very sensitive four-antenna VLBI array at the wavelength of 18cm. The distance to M100 and the expansion velocities are such that the supernova cannot be fully resolved by our Earth-wide array. Model-dependent sizes for the source have been determined and compared with pre

J. W. Taylor, J. A. Duffy, A. M. Bebb, M. R. Lees

Non-resonant ferromagnetic x-ray diffraction has been used to separate the spin and orbital contribution to the magnetization density of the proposed zero-moment ferromagnet $Sm_{0.982}Gd_{0.018} Al_{2}$. The alignment of the spin and orbital moments relative to the net magnetization shows a sign reversal at 84K, the compensation temperature. Below this temp

G. Odor, M. C. Marques, M. A. Santos

We investigated the phase transition behavior of a binary spreading process in two dimensions for different particle diffusion strengths ($D$). We found that $N>2$ cluster mean-field approximations must be considered to get consistent singular behavior. The $N=3,4$ approximations result in a continuous phase transition belonging to a single universality clas

Y. Hasegawa, R. Loidl, G. Badurek, M. Baron

Off-diagonal geometric phases acquired in the evolution of a spin-1/2 system have been investigated by means of a polarized neutron interferometer. Final counts with and without polarization analysis enable us to observe simultaneously the off-diagonal and diagonal geometric phases in two detectors. We have quantitatively measured the off-diagonal geometric

Nicola Manini, Giuseppe E. Santoro, Andrea Dal Corso, Erio Tosatti

Within dynamical mean-field theory, we study the metal-insulator transition of a twofold orbitally degenerate Hubbard model as a function of a splitting Δof the degeneracy. The phase diagram in the U-Δplane exhibits two-band and one-band metals, as well as the Mott insulator. The correlated two-band metal is easily driven to the insulator state by a striking

A. Alonso Izquierdo, W. Garcia Fuertes, M. A. Gonzalez Leon, J. Mateos Guilarte

A method for describing the quantum kink states in the semi-classical limit of several (1+1)-dimensional field theoretical models is developed. We use the generalized zeta function regularization method to compute the one-loop quantum correction to the masses of the kink in the sine-Gordon and cubic sinh-Gordon models and another two ${\rm P}(ϕ)_2$ systems w

Prabhakar Pradhan, S. Sridhar

We study the statistics of the experimental eigenfunctions of chaotic and disordered microwave billiards in terms of the moments of their spatial distributions, such as the Inverse Participation Ratio (IPR) and density-density auto-correlation. A path from chaos to disorder is described in terms of increasing IPR. In the chaotic, ballistic limit, the data co

V. Ravindran, J. Smith, W. L. van Neerven

We present the full next-to-leading order corrected differential distributions $d^2\sigma/dp_T/dy$, $d\sigma/dp_T$ and $d\sigma/dy$ for the semi-inclusive process $p + p\to H + 'X'$. Here $X$ denotes the inclusive hadronic state and $p_T$ and $y$ are the transverse momentum and rapidity of the Higgs-boson $H$ respectively. All QCD partonic subprocesses have

Nikolaos P. Papadakos

Classical and quantum information theory are simply explained. To be more specific it is clarified why Shannon entropy is used as measure of classical information and after a brief review of quantum mechanics it is possible to demonstrate why the density matrix is the main tool of quantum information theory. Then von Neumann entropy is introduced and with it

Maciej Kuna, Jan Naudts

We introduce photon theory following the same principles as for introduction of the quantum theory of a single particle, using a C*-algebraic approach based on covariance systems. The basic symmetries are additivity of the fields and additivity of test functions. We write down in explicit form a state of this covariance system. It turns out to reproduce the

R. T. Thew, K. Nemoto, A. G. White, W. J. Munro

Recently quantum tomography has been proposed as a fundamental tool for prototyping a few qubit quantum device. It allows the complete reconstruction of the state produced from a given input into the device. From this reconstructed density matrix, relevant quantum information quantities such as the degree of entanglement and entropy can be calculated. Genera

A. V. Demura, V. I. Kogan, A. B. Kukushkin, V. A. Rantsev-Kartinov

We discuss the opportunities of diagnosing the parameters of hypothetical &#34;wild cables&#34; in fusion plasmas via analyzing the Stark broadening of hydrogen spectral lines. The &#34;wild cables&#34; concept have suggested the observed long-lived skeletal structures in tokamaks and Z-pinches to be caused by a microdust-assembled skeleton. We present the r

Harshawardhan Wanare

We obtain gain of the probe field at multiple frequencies in a closed three-level V-type system using frequency modulated pump field. There is no associated population inversion among the atomic states of the probe transition. We describe both the steady-state and transient dynamics of this system. Under suitable conditions, the system exhibits large gain si

P. Danielewicz

Hadronic transport models may be utilized to extract bulk nuclear properties. Deduction of in-medium nucleon-nucleon cross sections and of nuclear viscosity is discussed, as well as the extraction of momentum dependence of nucleonic mean field. Moreover, determination of the nuclear incompressibility and of constraints on the nuclear pressure at supranormal

Thomas Schaefer

We review recent work on the phase structure of QCD at very high baryon density. We introduce the phenomenon of color superconductivity and discuss the use of weak coupling methods. We study the phase structure as a function of the number of flavors and their masses. We also introduce effective theories that describe low energy excitations at high baryon den

C. J. Lin, H. Q. Zhang, Z. H. Liu, Y. W. Wu

With the binding energies and configurations determined experimentally, the root-mean-square radii are calculated for a number of single-particle states by numerically solving the Sch{ö}rdinger equations. By studying the relations between the radii and separation energies, the new scaling laws and necessary conditions for neutron halos and proton halos are e

V. R. Shaginyan

The density functional determining the Coulomb energy of nuclei is calculated to the first order in $e^2$. It is shown that the Coulomb energy includes three terms: the Hartree energy; the Fock energy; and the correlation Coulomb energy (CCE), which contributes considerably to the surface energy, the mass difference between mirror nuclei, and the single-part

Y. Maeda, M. Segawa, H. P. Yoshida, M. Nomachi

The analyzing power of ${\vec p}p\to ppπ^0$ reaction has been measured at the beam energy of 390 MeV. The missing mass technique of final protons has been applied to identify the $π^0$ production event. The dependences of the analyzing power on the pion emission-angle and the relative momentum of the protons have beenobtained. The angular dependence could be

Gregory Eyink, Jack Xin

We study a system of semilinear hyperbolic equations passively advected by smooth white noise in time random velocity fields. Such a system arises in modeling non-premixed isothermal turbulent flames under single-step kinetics of fuel and oxidizer. We derive closed equations for one-point and multi-point probability distribution functions (PDFs) and closed f

A. E. Motter, Y. -C. Lai

We show that weak dissipation, typical in realistic situations, can have a metamorphic consequence on nonhyperbolic chaotic scattering in the sense that the physically important particle-decay law is altered, no matter how small the amount of dissipation. As a result, the previous conclusion about the unity of the fractal dimension of the set of singularitie

Michael A. Graber

The Lorentz force equations provide a partial description of the geodesic motion of a charged particle on a four-manifold. Under the hypothesis that Maxwell&#39;s equations express symmetry properties of the Ricci tensor, the full electromagnetic connection is determined. From this connection, the fourth equation of the geodesic is derived. The validity of t

W. Garcia Fuertes, A. M. Perelomov

We prove some new formulae for the derivatives of the generalized Gegenbauer polynomials associated to the Lie algebra $A_2$.

O. Vivolo

The purpose of this paper is to show that the monodromy of action variables of the Lagrange top and its generalizations can be deduced from the monodromy of cycles on a suitable hyperelliptic curve (computed by the Picard-Lefschetz formula).

Andras Nemethi, Liviu I. Nicolaescu

This is a continuation of our paper math.AG/0111298. We prove an explicit formula for the geometric genus p_g of a quasihomogeneous isolated surface singularity in terms of the Seiberg-Witten invariant of the link and other topological data which can be read from a resolution graph of the singularity. Moreover, we also determine all the Reidemeister-Turaev s

Alexandru Ioan Badulescu

We prove the Jacquet-Langlands local correspondence in non-zero characteristic, using the proof by Deligne, Kazhdan and Vignéras for the zero characteristic case and the theory of closed fields of Kazhdan. We also prove the orthogonality relations for an inner form of $GL_n$ in non-zero characteristic.

S. Yakovenko

We suggest an algorithm for derivation of the Picard--Fuchs system of Pfaffian equations for Abelian integrals corresponding to semiquasihomogeneous Hamiltonians. It is based on an effective decomposition of polynomial forms in the Brieskorn lattice. The construction allows for an explicit upper bound on the norms of the polynomial coefficients, an important