August 2001 arXiv papers — page 16
Showing 1,501–1,600 of 2,401 papers
Adrian L. Melott, Scott W. Chambers, Christopher J. Miller
We argue that there has been substantial evolution in the ellipticity of rich galaxy clusters between 0 < z < 0.1, and suggest that this is additional evidence for a low matter-density Universe.
Jesús Maíz-Apellániz
We have retrieved multicolor WFPC2/HST data from the STScI archive for 27 nearby Massive (>= 3x10^4 M_Sun) Young (< 20 Myr) star Clusters (MYCs). The data represents the most-complete-to-date sample of clearly resolved MYCs. We have analyzed their structural properties and have found that they can be classified as either Super Star Clusters (SSCs) or as Scal
Emily L. Schaller, Robert A. Fesen
The kinematic and morphological properties of a string of [Ar III] bright knots in the Crab Nebula are examined using 1994 - 1999 HST WFPC-2 images of the remnant. We find that five southern [Ar III] bright knots exhibit ordinary radial motions away from the nebula's center of expansion with magnitudes consistent with their projected radial displacements
A. J. Benson, C. S. Frenk, C. G. Lacey, C. M. Baugh
We use a self-consistent model of galaxy formation and the evolution of the intergalactic medium to study the effects of the reionization of the universe at high redshift on the properties of satellite galaxies like those seen around the Milky Way. Photoionization suppresses the formation of small galaxies, so that surviving satellites are preferentially tho
A. J. Benson, C. G. Lacey, C. M. Baugh, S. Cole
We develop a coupled model for the evolution of the global properties of the intergalactic medium (IGM) and the formation of galaxies, in the presence of a photoionizing background due to stars and quasars. We use this model to predict the thermodynamic history of the IGM when photoionized by galaxies forming in a cold dark matter (CDM) universe. The evoluti
3-Gyr-old Globular Clusters in the Merger Remnant NGC 1316: Implications for the Fate of Globular Clusters Formed During Gas-rich Galaxy Mergers
astro-phPaul Goudfrooij
The giant early-type merger remnant galaxy NGC 1316 is an ideal probe for studying the long-term effects of a major merger on its globular cluster (GC) system, given its spectroscopically derived merger age of 3 Gyr which we reported in a recent paper. Here we report several pieces of photometric evidence showing that the second-generation GCs in NGC 1316 ar
M. C. Smith, S. Mao, P. R. Wozniak
We present a systematic search for parallax microlensing events among a total of 512 microlensing candidates in the OGLE II database for the 1997-1999 seasons. We fit each microlensing candidate with both the standard microlensing model and also a parallax model that accounts for the Earth's motion around the Sun. We then search for the parallax signatur
Negative intensity patches in angular variations of CMB as a probe of the period of reionization
astro-phA. Doroshkevich, V. Dubrovich
The observational tests for the period of reionization of the universe are discussed. We show that this period can be observed as {\it negative} intensity patches of the CMB radiation with the amplitude $δT/T\sim 10^{-5}$ and the angular sizes $θ_T\sim$10 angular seconds in range of the wavelength 0.1 cm$\leqλ\leq$1 cm. The expected number density and freque
B. M. Poggianti, T. Bridges, D. Carter, B. Mobasher
The ages of stellar populations in 52 elliptical and S0 galaxies in the Coma cluster are investigated using a new spectroscopic sample. More than 40% of the S0s are found to have experienced recent star formation in their central regions during the last ~5 Gyrs, while such activity is absent in the ellipticals. Galaxies in this sample have absolute magnitude
Jozef Klacka
Relativistically covariant form of equation of motion for real particle (neutral in charge) under the action of electromagnetic radiation is derived. Various formulations of the equation of motion in the proper frame of reference of the particle are used. Main attention is devoted to the reformulation of the equation of motion in the general frame of referen
Jozef Klacka
Detailed discussion of university textbook statements (Harwit 1988) concerning the Poynting-Robertson effect (P-R effect) is presented. Discussion is concentrated on better physical understanding of the P-R effect. References to complete correct equation of motion for real dust particle are also presented.
Herman L. Marshall, Claude R. Canizares, Norbert S. Schulz
We present observations of SS 433 using the Chandra High Energy Transmission Grating Spectrometer. Many emission lines of highly ionized elements are detected with the relativistic blue and red Doppler shifts. The lines are measurably broadened to 1700 km/s (FWHM) and the widths do not depend significantly on the characteristic emission temperature, suggesti
Rodger I. Thompson, Ranga-Ram Chary, Michael R. Corbin, Harland Epps
This paper presents NICMOS images of the nucleus and emission line regions in NGC 1068. The location of the nucleus relative to the emission line features is established and the physics underlying the morphology is discussed.
M. A. Voronkov, V. I. Slysh
We report results of EVN interferometric study of two star-forming regions L1206 and GL2789 in the brightest methanol maser line at 6.7 GHz. Using measured absolute positions both methanol masers were identified with protostars which are sources of bipolar outflows. Both masers consist of several maser spots, with some of them being aligned in a linear struc
Emory F. Bunn
[NOTE: Previous versions of this paper (both on astro-ph and published in Phys. Rev. D) contain results that are in error. The power spectra C_l were normalized incorrectly by a factor of 2 pi. All observing times in detector-years in those versions are too large by a factor of 2 pi. The main place these numbers appear is on the vertical axes of Figures 4 an
Norbert S. Schulz, Deepto Chakrabarty, Herman L. Marshall, Claude R. Canizares
We report on a 39 ks observation of the 7.7-s low-mass X-ray binary pulsar 4U1626-67 with the High Energy Transmission Grating Spectrometer (HETGS) on the Chandra X-Ray Observatory. This ultracompact system consists of a disk-accreting magnetic neutron star and a very low mass, hydrogen-depleted companion in a 42-min binary. We have resolved the previously r
H. C. Spruit
Magnetic fields can be created in stably stratified (non-convective) layers in a differentially rotating star. A magnetic instability in the toroidal field (wound up by differential rotation) replaces the role of convection in closing the field amplification loop. Tayler instability is likely to be the most relevant magnetic instability. A dynamo model is de
Marcus Pivato, Reem Yassawi
If M is a monoid (e.g. the lattice Z^D), and A is an abelian group, then A^M is a compact abelian group; a linear cellular automaton (LCA) is a continuous endomorphism F:A^M --> A^M that commutes with all shift maps. If F is diffusive, and mu is a harmonically mixing (HM) probability measure on A^M, then the sequence {F^N mu} (N=1,2,3,...) weak*-converges to
Marcus Pivato, Reem Yassawi
Let M be a monoid (e.g. the lattice Z^D), and A an abelian group. A^M is then a compact abelian group; a linear cellular automaton (LCA) is a continuous endomorphism F:A^M --> A^M that commutes with all shift maps. Let mu be a (possibly nonstationary) probability measure on A^M; we develop sufficient conditions on mu and F so that the sequence {F^N mu} (N=1,
Joaquim Gomis, Toni Mateos
We construct supergravity duals of D6-branes wrapping Kahler four-cycles inside a Calabi-Yau threefold, CY_3. We obtain the purely gravitational M-theory description, which turns out to be a Calabi-Yau fourfold, CY_4. We also analyze the dynamics of a probe D6 in this background.
Observational Constraints on the Self Interacting Dark Matter Scenario and the Growth of Supermassive Black Holes
astro-phJoseph F. Hennawi, Jeremiah P. Ostriker
We consider the consequences of SIDM for a velocity dependent cross section per unit mass. Accretion of SIDM onto seed black holes can produce supermassive black holes that are too large for certain combinations of parameters,which is used to obtain a new constraint on the dark matter interaction. Constraints due to other considerations are presented and pre
Schmidt number of pure states in bipartite quantum systems as an algebraic-geometric invariant
quant-phHao Chen
Our previous work about algebraic-geometric invariants of the mixed states are extended and a stronger separability criterion is given. We also show that the Schmidt number of pure states in bipartite quantum systems, a classical concept, is actually an algebraic-geometric invariant.
Hao Chen
We introduce algebraic sets in the products of complex projective spaces for the mixed states in multipartite quantum systems as their invariants under local unitary operations. The algebraic sets have to be the union of the linear subspaces if the state is separable. Some examples are studied based on our criterion
Hao Chen
We introduce algebraic sets in the complex projective spaces for the mixed states in bipartite quantum systems as their invariants under local unitary operations. The algebraic sets of the mixed state have to be the union of the linear subspaces if the mixed state is separable. Some examples are given and studied based on our criterion
DMSO-Induced Dehydration of DPPC Membranes Studied by X-ray Diffraction, Small-Angle Neutron Scattering, and Calorimetry
physics.bio-phM. A. Kiselev, P. Lesieur, A. M. Kisselev, C. Grabielle-Madelmond
The influence of dimethyl sulfoxide (DMSO) on membrane thickness, multilamellar repeat distance, and phase transitions of 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC) was investigated by X-ray diffraction and small-angle neutron scattering (SANS). The differential scanning calorimetry (DSC) study of water freezing and ice melting was performed in
On Whether People Have the Capacity to Make Observations of Mutually Exclusive Physical Phenomena Simultaneously
physics.gen-phD. M. Snyder
It has been shown by Einstein, Podolsky, and Rosen that in quantum mechanics either one of two different wave functions predicting specific values for quantities represented by non-commuting Hermitian operators can characterize the same physical existent, without a physical interaction responsible for which wave function occurs. This result means that one ca
Self-localization of laser induced tumor coagulation limited by heat diffusion through active tissue
nlin.AOB. Y. Datsko, V. V. Gafiychuk, I. A. Lubashevsky, A. V. Priezzhev
We analyze the necrosis growth due to thermal coagulation induced by laser light absorption and limited by heat diffusion into the surrounding live tissue. The tissue is assumed to contain a certain tumor in the undamaged tissue whereof the blood perfusion rate does not change during the action. By contrast, the normal tissue responds strongly to increase in
D. Blömker, Jinqiao Duan, T. Wanner
Enstrophy is an averaged measure of fluid vorticity. This quantity is particularly important in {\em rotating} geophysical flows. We investigate the dynamical evolution of enstrophy for large-scale quasi-geostrophic flows under random wind forcing. We obtain upper bounds on the enstrophy, as well as results establishing its Hölder continuity and describing t
Hongjun Gao, Jinqiao Duan
The ocean thermohaline circulation, also called meridional overturning circulation, is caused by water density contrasts. This circulation has large capacity of carrying heat around the globe and it thus affects the energy budget and further affects the climate. We consider a thermohaline circulation model in the meridional plane under external wind forcing.
Marcus Pivato
If A is a finite alphabet, Z^D is a D-dimensional lattice, U is a subset of Z^D, and mu_U is a probability measure on A^U that ``looks like'' the marginal projection of a stationary random field on A^(Z^D), then can we ``extend'' mu_U to such a field? Under what conditions can we make this extension ergodic, (quasi)periodic, or (weakly) mixin
Benoit Rivet
A classical result of Sampson and Schoen-Yau in 1978 states that every diffeomorphism between compact hyperbolic Riemann surfaces is homotopic to an harmonic diffeomorphism. As conjectured by Schoen in 1993 and partially proved by Wan in 1992 and Tam-Wan in 1995, we prove in this article that this theorem generalizes to the non compact case : every quasi sym
J. W. Moffat
An M-theory constructed in an eleven-dimensional supermanifold with a <>-product of field operators is shown to have a de Sitter space solution. Possible implications of this result for cosmology are mentioned.
Marek Karliner
We sketch some recent ideas proposed as the mechanism behind the puzzling experimental results on baryon-antibaryon production in e+e- annihilation close to threshold. The essential new point in the proposed mechanism is that it is a two-stage process, with a coherent state of pions serving as an intermediary between e+e- and the baryon-antibaryon system. Sk
M. Göckeler, R. Horsley, D. Pleiter, P. E. L. Rakow
In this talk we highlight recent lattice calculations of the nucleon form factors and structure functions.
J. V. Tucker, J. I. Zucker
A model of computation is abstract if, when applied to any algebra, the resulting programs for computable functions and sets on that algebra are invariant under isomorphisms, and hence do not depend on a representation for the algebra. Otherwise it is concrete. Intuitively, concrete models depend on the implementation of the algebra. The difference is partic
Possible evidence for the existence of the Fehrenbacher-Rice band: O K-edge XANES study on Pr1-xCaxBa2Cu3O7
cond-mat.supr-conI. P. Hong, J. -Y. Lin, J. M. Chen, S. Chatterjee
X-ray absorption near edge structure (XANES), resistivity and thermoelectric power have been measured on Pr1-xCaxBa2Cu3O7. These data reveal an intriguing electronic structure in Pr-doped cuprates. The absorption peak in XANES associated with the Fehrenbacher-Rice (FR) band has been identified. The Ca-doped holes in Pr1-xCaxBa2Cu3O7 go to both the Zhang-Rice
J. Richard Bond, Robert G. Crittenden
We describe the subject of Cosmic Microwave Background (CMB) analysis - its past, present and future. The theory of Gaussian primary anisotropies, those arising from linear physics operating in the early Universe, is in reasonably good shape so the focus has shifted to the statistical pipeline which confronts the data with the theory: mapping, filtering, com
Mir Abbas Jalali, P. Tim de Zeeuw
We construct phase-space distribution functions for the oblate, cuspy mass models of Sridhar & Touma, which may contain a central point mass (black hole) and have potentials of Stäckel form in parabolic coordinates. The density in the ST models is proportional to a power $r^{-γ}$ of the radius, with $0<γ<1$. We derive distribution functions $f(E, L_z)$ for t
Cosmological Aspects of Gamma-Ray Bursts: Luminosity Evolution and an Estimate of the Star Formation Rate at High Redshifts
astro-phNicole M. Lloyd-Ronning, Chris L. Fryer, Enrico Ramirez-Ruiz
Using 220 Gamma-Ray Burst (GRB) redshifts and luminosities derived from the luminosity-variability relationship of Fenimore & Ramirez-Ruiz (2000), we show that there exists a significant correlation between the GRB luminosity and redshift. In particular, we find that the evolution of the average luminosity can be parameterized as L ~ (1+z)^(1.4 +- 0.5), wher
Calculation of Non-Leptonic Kaon Decay Amplitudes from $K\toπ$ Matrix Elements in Quenched Domain-Wall QCD
hep-latPACS Collaboration, J. Noaki, S. Aoki, Y. Aoki
We explore application of the domain wall fermion formalism of lattice QCD to calculate the $K\toππ$ decay amplitudes in terms of the $K\toπ$ and $K\to 0$ hadronic matrix elements through relations derived in chiral perturbation theory. Numerical simulations are carried out in quenched QCD using domain-wall fermion action for quarks and an RG-improved gauge
Tetsuya Takaishi, Philippe de Forcrand
We discuss hybrid Monte Carlo algorithms for odd-flavor lattice QCD simulations. The algorithms include a polynomial approximation which enables us to simulate odd-flavor QCD in the framework of the hybrid Monte Carlo algorithm. In order to make the algorithms exact, the correction factor to the polynomial approximation is also included in an economical, sto
Namiko Mitarai, Hisao Hayakawa, Hiizu Nakanishi
We show that a micropolar fluid model successfully describes collisional granular flows on a slope. A micropolar fluid is the fluid with internal structures in which coupling between the spin of each particle and the macroscopic velocity field is taken into account. It is a hydrodynamical framework suitable for granular systems which consists of particles wi
Rabin Banerjee, Pradip Mukherjee
We provide a new canonical approach for studying the quantum mechanical damped harmonic oscillator based on the doubling of degrees of freedom approach. Explicit expressions for Lagrangians of the elementary modes of the problem, characterising both forward and backward time propagations are given. A Hamiltonian analysis, showing the equivalence with the Lag
T. Plefka
The stability of the TAP mean field equations is reanalyzed with the conclusion that the exclusive reason for the breakdown at the spin glass instability is an inconsistency for the value of the local susceptibility. A new alternative approach leads to modified equations which are in complete agreement with the original ones above the instability. Essentiall
Satoru Saito, Akira Shudo, Jun-ichi Yamamoto, Katsuhiko Yoshida
For a given differentiable map $(x,y)\to (X(x,y),Y(x,y))$, which has an inverse, we show that there exists a Hamiltonian flow in which x plays the role of the time variable while y is fixed.
Terry Rudolph, Jian-Wei Pan
We describe a simple scheme for implementing the non-linear sign gate of Knill, Laflamme and Milburn (Nature, {\bf 409}, 46-52, Jan. 4 (2001)) which forms the basis of an experiment underway at the University of Vienna.
Satoru Saito, Noriko Saitoh, Jun-ichi Yamamoto, Katsuhiko Yoshida
We propose a method to characterize discrete time evolution equations, which generalize discrete time soliton equations, including the $q$-difference Painlevé IV equations discussed recently by Kajiwara, Noumi and Yamada.
T A Larsson
Dual Pfaff equations (of the form \tilde D^a = 0, \tilde D^a some vector fields of degree -1) preserved by the exceptional infinite-dimensional simple Lie superalgebras ksle(5|10), vle(3|6) and mb(3|8) are constructed, yielding an intrinsic geometric definition of these algebras. This leads to conditions on the vector fields, which are solved explicitly. Exp
Weighted Completion of Galois Groups and Galois Actions on the Fundamental Group of P^1 - {0,1,infinity}
math.AGRichard Hain, Makoto Matsumoto
This is a revision of the paper that was previously entitled "Weighted Completion of Galois Groups and Some Conjectures of Deligne". Fix a prime number $ł$. We prove a conjecture stated by Ihara, which he attributes to Deligne, about the action of the absolute Galois group on the pro-$ł$ completion of the fundamental group of the thrice punctured pro
Badis Ydri
In this talk we will report on few results of discrete physics on the fuzzy sphere . In particular non-trivial field configurations such as monopoles and solitons are constructed on fuzzy ${\bf S}^2$ using the language of K-theory, i.e projectors . As we will show, these configurations are intrinsically finite dimensional matrix models . The corresponding mo
A. Chenaghlou
The sinh-Gordon model on a half-line with integrable boundary conditions is considered in low order perturbation theory developed in affine Toda field theory. The quantum corrections to the classical reflection factor of the model are studied up to the second order in the difference of the two boundary parameters and to one loop order in the bulk coupling. I
Mauricio Bellini
The possible amplification of gauge invariant metric fluctuations in the infrared sector are very important during reheating stage of inflation. In this stage the inflaton oscillates arount the minimum of the scalar potential. The evolution for super Hubble scales gauge invariant metric fluctuations can be studied by means of the Bardeen parameter. For a mas
Seth A. Major, Kevin L. Setter
We present an argument that, for a large class of possible dynamics, a canonical quantization of gravity will satisfy the Bekenstein-Hawking entropy-area relation. This result holds for temperatures low compared to the Planck temperature and for boundaries with areas large compared to Planck area. We also relate our description, in terms of a grand canonical
Zhixin Qian, Giovanni Vignale
We derive the spin-wave dynamics of a magnetic material from the time-dependent spin density functional theory in the linear response regime. The equation of motion for the magnetization includes, besides the static spin stiffness, a "Berry curvature" correction and a damping term. A gradient expansion scheme based on the homogeneous spin-polarized e
O. P. Martynenko, V. V. Makhro, I. G. Makhro
"Phase transitions" between quantum and classical behaviour in large spin magnetic systems discused.
J. W. Moffat
The problem of explaining the acceleration of the expansion of the universe and the observational and theoretical difficulties associated with dark matter and dark energy are discussed. The possibility that GR does not correctly describe the large-scale structure of the universe is considered and an alternative gravity theory is proposed as a possible resolu
Leo Girardi
I briefly introduce a database of models that describe the evolution of star clusters in several broad-band photometric systems. Models are based on the latest Padova stellar evolutionary tracks - now including the alpha-enhanced case and improved AGB models - and a revised library of synthetic spectra from model atmospheres. As of today, we have revised iso
J. Hwang, H. Noh
The scalar field with an exponential potential allows a scaling solution where the the density of the field follows the density of the dominating fluid. Such a scaling regime is often used as an important ingredient in many models of quintessence. We analyse evolution of perturbations while the background follows the scaling. As the results, the perturbed sc
D. L. Kaplan, D. W. Fox, S. R. Kulkarni, E. V. Gotthelf
We present observations of the Soft Gamma-ray Repeater SGR 1806-20 taken with the Chandra X-ray Observatory. We identify the X-ray counterpart of SGR 1806-20 based on detection of 7.5-s pulsations. Using three unrelated X-ray sources (and USNO stars) as position references, we are able to determine that the SGR is at alpha_{2000}=18h08m39.32s and delta_{2000
I. A. Stepanov
It is shown that the electron wave vector in a crystal cannot be smaller than a certain value. As a result, in a crystal there are many first Brillouin zones, and not only one as it had been supposed earlier. In crystal there can be many electrons with the same wave vector, and not only two as it had been supposed earlier. These electrons must be at sufficie
A. Adams, J. Polchinski, E. Silverstein
We consider closed string tachyons localized at the fixed points of noncompact nonsupersymmetric orbifolds. We argue that tachyon condensation drives these orbifolds to flat space or supersymmetric ALE spaces. The decay proceeds via an expanding shell of dilaton gradients and curvature which interpolates between two regions of distinct angular geometry. The
Maciej Dunajski
It is shown how solutions to the Tzitzéica equation can be used to construct a family of (pseudo) hyper-complex metrics in four dimensions.
Optical second harmonic generation near a black hole horizon as possible source of experimental information on quantum gravitational effects
astro-phIgor I. Smolyaninov
Optical second harmonic generation near a black hole horizon is suggested as a source of experimental information on quantum gravitational effects. While absent in the framework of general relativity, second harmonic generation appears in the toy models of sonic and electromagnetic black holes, where spatial dispersion at high frequencies for waves boosted t
Mark E. Fels, Charles G. Torre
We consider a version of Palais' Principle of Symmetric Criticality (PSC) that is applicable to the Lie symmetry reduction of Lagrangian field theories. PSC asserts that, given a group action, for any group-invariant Lagrangian the equations obtained by restriction of Euler-Lagrange equations to group-invariant fields are equivalent to the Euler-Lagrange
SN1987A and the Status of Oscillation Solutions to the Solar Neutrino Problem (including an appendix discussing the NC and day/night data from SNO)
hep-phM. Kachelriess, A. Strumia, R. Tomas, J. W. F. Valle
We study neutrino oscillations and the level-crossing probability PLZ in power-law potential profiles A(r)\propto r^n. We give local and global adiabaticity conditions valid for all mixing angles theta and discuss different representations for PLZ. For the 1/r^3 profile typical of supernova envelopes we compare our analytical to numerical results and to earl
Hang-Bae Kim, Jihn E. Kim
The axino with mass in the GeV region can be cold dark matter(CDM) in the galactic halo. However, if R-parity is broken, for example by the bilinear terms $μ_α$, then axino($\tilde a$) can decay to $ν+γ$. In this case, the most stringent bound on the axino lifetime comes from the diffuse photon background and we obtain that the axino lifetime should be great
P. N. Deepak, G. Ramachandran
The singlet and triplet differential cross sections for pp-> pp pi^0 have been estimated for the first time at 325, 350, 375 and 400 MeV using the results of the recent experimental measurements [Phys. Rev. C 63, 064002 (2001)] of Meyer et al.
N. A. Smirnova, N. Pietralla, A. Leviatan, J. N. Ginocchio
A generalized M1 sum rule for orbital magnetic dipole strength from excited symmetric states to mixed-symmetry states is considered within the proton-neutron interacting boson model of even-even nuclei. Analytic expressions for the dominant terms in the B(M1) transition rates from the first and second $2^+$ states are derived in the U(5) and SO(6) dynamic sy
The Las Campanas Infrared Survey. III. The H-band Imaging Survey and the Near-Infrared and Optical Photometric Catalogs
astro-phHsiao-Wen Chen, P. J. McCarthy, R. O. Marzke, J. Wilson
(Abridged) The Las Campanas Infrared Survey, based on broad-band optical and near-infrared photometry, is designed to robustly identify a statistically significant and representative sample of evolved galaxies at redshifts z>1. We have completed an H-band imaging survey over 1.1 square degrees of sky in six separate fields. The average 5 sigma detection limi
Donam Youm
We study a scalar-tensor bimetric cosmology in the Randall-Sundrum model with one positive tension brane, where the biscalar field is assumed to be confined on the brane. The effective Friedmann equations on the brane are obtained and analyzed. We comment on resolution of cosmological problems in this bimetric model.
Margaret Symington
We prove that the generalized rational blowdown, a surgery on smooth 4-manifolds, can be performed in the symplectic category.
Subir Sarkar, Ramon Toldra
It has been speculated that the recently detected ultra-high energy cosmic rays may originate from the decays of relic particles with mass of order $10^{12}$ GeV clustered in the halo of our Galaxy. This hypothesis can be tested through forthcoming measurements of the spectra of both high energy cosmic nucleons and neutrinos, which are determined in this mod
Separately contacted edge states: A new spectroscopic tool for the investigation of the quantum Hall effect
cond-mat.mes-hallA. Wuertz, R. Wildfeuer, A. Lorke, E. V. Deviatov
Using an innovative combination of a quasi-Corbino sample geometry and the cross-gate technique, we have developed a method that enables us to separately contact single edge channels in the quantum Hall regime and investigate equilibration among them. Performing 4-point resistance measurements, we directly obtain information on the energetic and geometric st
C. A. Terrero-Escalante, A. A. Garcia
Recently it was argued that an inflationary potential yielding power spectra characterized by a scale-invariant tensorial spectral index and a weakly scale-dependent scalar spectral index might account for a generic large-scale structure formation in the multiverses scenario of eternal inflation. Here it is shown that this statement remains true if the tenso
K. M. Mertes, M. P. Sarachik, Y. Paltiel, H. Shtrikman
We report Hall sensor measurements of the magnetic relaxation of Mn$_{12}$-acetate as a function of magnetic field applied along the easy axis of magnetization for a series of closely-spaced temperatures between 0.24 K and 1.9 K. We map out a region in the $H-T$ plane where ground state tunneling is observed, a region where tunneling proceeds via thermally-a
Comparison of two non-primitive methods for path integral simulations: Higher-order corrections vs. an effective propagator approach
cond-matFlorian R. Krajewski, Martin H. Muser
Two methods are compared that are used in path integral simulations. Both methods aim to achieve faster convergence to the quantum limit than the so-called primitive algorithm (PA). One method, originally proposed by Takahashi and Imada, is based on a higher-order approximation (HOA) of the quantum mechanical density operator. The other method is based upon
Hai-Yang Cheng
The recent measurements of the color-suppressed modes $\bar B^0\to D^{(*)0}π^0$ imply non-vanishing relative final-state interaction (FSI) phases among various $\bar B\to Dπ$ decay amplitudes. Depending on whether or not FSIs are implemented in the topological quark-diagram amplitudes, two solutions for the parameters $a_1$ and $a_2$ are extracted from data
Ji-Woo Lee, Min-Chul Cha, Doochul Kim
We study the zero-temperature phase transition of a two-dimensional disordered boson Hubbard model. The phase diagram of this model is constructed in terms of the disorder strength and the chemical potential. Via quantum Monte Carlo simulations, we find a multicritical line separating the weak-disorder regime, where a random potential is irrelevant, from the
The Las Campanas IR Survey. II. Photometric redshifts, comparison with models and clustering evolution
astro-phA. E. Firth, R. S. Somerville, R. G. McMahon, O. Lahav
The LCIR Survey, using the Cambridge IR Survey Instrument (CIRSI), reaches H \~ 20-21 over ~1 deg^2. We present results for 744 arcmin^2 in which public UBVRI data exist. We compare optical-IR colours with predictions of a semi-analytic hierarchical model (SAM) and find reasonable agreement. We also determine photometric redshifts, finding a median z of z_m
J. Polonyi, K. Sailer
The effective action for the charge density and the photon field is proposed as a generalization of the density functional. A simple definition is given for the density functional, as the functional Legendre transform of the generator functional of connected Green functions for the density and the photon field, offering systematic approximation schemes. The
On the structure of the virtual Compton amplitude with additional final-state meson in the extended Bjorken region
hep-phJohannes Blümlein, Jörg Eilers, Bodo Geyer, Dieter Robaschik
Using the framework of the non-local light-cone expansion a systematic study is performed for the structure of the twist-2 contributions to the virtual Compton amplitude in polarized deep-inelastic non-forward scattering for general nucleon spin with an additional scalar meson in the final state. A useful kinematic parameterization allowing for appropriate t
Nicolas Borghini, Yves Gouverneur, Michel H. G. Tytgat
The restrictions imposed by anomaly cancellation on the chiral fermion content of nonsupersymmetric gauge theories based on various groups are studied in spacetime dimension D=6, 8, and 10. In particular, we show that the only mathematically consistent chiral SU(5) theory in D=6 contains three nonidentical generations.
Kondo effect of impurity moments in d-wave superconductors: Quantum phase transition and spectral properties
cond-mat.str-elMatthias Vojta, Ralf Bulla
We discuss the dynamics of magnetic moments in d-wave superconductors, in particular we focus on moments induced by doping non-magnetic impurities into cuprates. The interaction of such moments with the Bogoliubov quasiparticles of the superconductors can be decribed by variants of the pseudogap Kondo model, characterized by a power-law density of states at
Hans C Fogedby
A growing interface subject to noise is described by the Kardar-Parisi-Zhang equation or, equivalently, the noisy Burgers equation. In one dimension this equation is analyzed by means of a weak noise canonical phase space approach applied to the associated Fokker-Planck equation. The growth morphology is characterized by a gas of nonlinear soliton modes with
Consistent refinement of Bethe strings for spin and electron models and a new non-Bethe solution
cond-matAnjan Kundu
Well known Bethe strings in spin chains, delta-electron gas, Hubbard and t-J models are shown to be imprecise, while their consisten refinement along with a new non-Bethe r-string are discovered. Connection with the earlier results is established and the string hypothesis problem is discussed in the light of the present findings.
Licia Verde, David N. Spergel
We compute the cosmic microwave background bispectrum arising from the cross-correlation of primordial, lensing and Rees-Sciama signals. The amplitude of the bispectrum signal is sensitive to the matter density parameter, Omega_0, and the equation of state of the dark energy, which we parameterize by w_Q. We conclude that the dataset of the Atacama Cosmology
Exactly Solvable Matrix Models for the Dynamical Generation of Space-Time in Superstring Theory
hep-thJun Nishimura
We present a class of solvable SO(D) symmetric matrix models with D bosonic matrices coupled to chiral fermions. The SO(D) symmetry is spontaneously broken due to the phase of the fermion integral. This demonstrates the conjectured mechanism for the dynamical generation of four-dimensional space-time in the IIB matrix model, which was proposed as a nonpertur
Compromise of Localized Graviton with a Small Cosmological Constant in Randall-Sundrum Scenario
hep-thD. K. Park, S. Tamaryan
A new mechanism which leads to a linearized massless graviton localized on the brane is found in the $AdS$/CFT setting, {\it i.e.} in a single copy of $AdS_5$ spacetime with a singular brane on the boundary, within the Randall-Sundrum brane-world scenario. With an help of a recent development in path-integral techniques, a one-parameter family of propagators
Soft Mode Dynamics Above and Below the Burns Temperature in the Relaxor Pb(Mg_1/3Nb_2/3)O_3
cond-mat.mtrl-sciP. M. Gehring, S. Wakimoto, Z. -G. Ye, G. Shirane
We report neutron inelastic scattering measurements of the lowest-energy transverse optic (TO) phonon branch in the relaxor Pb(Mg_1/3Nb_2/3)O_3 from 400 to 1100 K. Far above the Burns temperature T_d ~ 620 K we observe well-defined propagating TO modes at all wave vectors q, and a zone center TO mode that softens in a manner consistent with that of a ferroel
On efficiency of critical-component method for solving singular and ill-posed systems of linear algebraic equations
math.RAG. A. Emel'yanenko, M. G. Emelianenko, T. T. Rakhmonov, E. B. Dushanov
Results are expoundd for the investigation of efficiency of the critical-component method for solving degenerate and ill-posed systems of linear algebraic equations
Davide Guzzetti
We study the analytic properties and the critical behavior of the elliptic representation of solutions of the Painlevé 6 equation. We solve the connection problem for elliptic representation in the generic case and in a non-generic case equivalent to WDVV equations of associativity.
Yu. Dabaghian, R. V. Jensen, R. Blümel
We present quantum graphs with remarkably regular spectral characteristics. We call them {\it regular quantum graphs}. Although regular quantum graphs are strongly chaotic in the classical limit, their quantum spectra are explicitly solvable in terms of periodic orbits. We present analytical solutions for the spectrum of regular quantum graphs in the form of
Quantum algorithm for finding periodicities in the spectrum of a black-box Hamiltonian or unitary transformation
quant-phDominik Janzing, Thomas Beth
Estimating the eigenvalues of a unitary transformation U by standard phase estimation requires the implementation of controlled-U-gates which are not available if U is only given as a black box. We show that a simple trick allows to measure eigenvalues of U\otimes U^\dagger even in this case. Running the algorithm several times allows therefore to estimate t
Dominik Janzing
The well-known algorithm for quantum phase estimation requires that the considered unitary is available as a conditional transformation depending on the quantum state of an ancilla register. We present an algorithm converting an unknown n-qubit pair-interaction Hamiltonian into a conditional one such that standard phase estimation can be applied to measure t
P. T. Cochrane, T. C. Ralph, G. J. Milburn
We show, by making conditional measurements on the Einstein-Podolsky-Rosen (EPR) squeezed vacuum, that one can improve the efficacy of teleportation for both the position difference, momentum sum and number difference, phase sum continuous variable teleportation protocols. We investigate the relative abilities of the standard and conditional EPR states, and
Existence of the Wigner function with correct marginal distributions along tilted lines on a lattice
quant-phMinoru Horibe, Akiyoshi Takami, Takaaki Hashimoto, Akihisa Hayashi
In order to determine the Wigner function uniquely, we introduce a new condition which ensures that the Wigner function has correct marginal distributions along tilted lines. For a system in $N$ dimensional Hilbert space, whose "phase space" is a lattice with $N^2$ sites, we get different results depending on whether $N$ is odd or even. Under the new
Alexander N. Gorban, Andrey Yu. Zinovyev, Tatyana G. Popova
An approach based on using the idea of distinguished coding phase in explicit form for identification of protein-coding regions (exons) in whole genome has been proposed. For several genomes an optimal window length for averaging GC-content function and calculating codon frequencies has been found. Self-training procedure based on clustering in multidimensio
Thomas Barford, Michael C. Birse
We apply the renormalisation-group to two-body scattering by a combination of known long-range and unknown short-range forces. A crucial feature is that the low-energy effective theory is regulated by applying a cut-off in the basis of distorted waves for the long range potential. We illustrate the method by applying it to scattering in the presence of a rep
A. Andronic, FOPI Collaboration
We present experimental data on directed flow in semi-central Au+Au collisions at incident energies from 90 to 400 A MeV. For the first time for this energy domain, the data are presented in a transverse momentum differential way. We study the first order Fourier coefficient v1 for different particle species and establish a gradual change of its patterns as
Martin Scharlemann
In math.GT/0106017 it was shown that thin position on Heegaard spines can be a useful tool for analyzing the topology of knots in 3-space. The proof there (specifically, of the Goda-Teragaito conjecture) requires masses of technical detail; it is easy to lose track of the underlying ideas. The present paper gives an overview of the argument, stripped of tech