April 2013 arXiv papers — page 70
Showing 6,901–7,000 of 7,616 papers
Carl J. Grillmair, Roc Cutri, Frank J. Masci, Tim Conroy
Combining the Wide-Field Infrared Survey Explorer All-Sky Release with the 2MASS Point Source Catalog, we detect a nearby, moderately metal-poor stellar debris stream spanning 24 degrees across the southern sky. The stream, which we designate Alpheus, is at an estimated distance of ~1.9 kpc. Its position, orientation, width, estimated metallicity, and to som
Decay coupling constant sum rules for tetraquarks $\bm{T[(\bar{Q}q)(Q\bar{q})]}$ with broken SU(3) symmetry
hep-phV. Gupta, G. Sánchez-Colón, S. Rajpoot
For tetraquarks of the form $T[(\bar{Q}q)(Q\bar{q})]$ we give sum rules for their decay coupling constants, taking into account the SU(3) symmetry breaking interactions to first order.
Characterizing the Cool KOIs. V. KOI-256: A Mutually Eclipsing Post-Common Envelope Binary
astro-ph.SRPhilip S. Muirhead, Andrew Vanderburg, Avi Shporer, Juliette Becker
We report that Kepler Object of Interest 256 (KOI-256) is a mutually eclipsing post-common envelope binary (ePCEB), consisting of a cool white dwarf (M = 0.592 +/- 0.089 MSun, R = 0.01345 +/- 0.00091 RSun, Teff = 7100 +/- 700 K) and an active M3 dwarf (M = 0.51 +/- 0.16 MSun, R = 0.540 +/- 0.014 RSun, Teff = 3450 +/- 50 K) with an orbital period of 1.37865 +
David A. Huse, Rahul Nandkishore, Vadim Oganesyan, Arijeet Pal
Closed quantum systems with quenched randomness exhibit many-body localized regimes wherein they do not equilibrate even though prepared with macroscopic amounts of energy above their ground states. We show that such localized systems can order in that individual many-body eigenstates can break symmetries or display topological order in the infinite volume l
The star formation rate and stellar mass limits for submillimetre galaxies implied by recent interferometric observations
astro-ph.COChristopher C. Hayward
Explaining the observed number counts of submillimetre (submm) galaxies (SMGs) has been a longstanding challenge for theoretical models. Surprisingly, recent observations have suggested that the brightest SMGs are almost exclusively multiple fainter sources blended into a single source in the single-dish surveys. This result is in contrast with the predictio
The VMC survey VII. Reddening map of the 30 Doradus field and the structure of the cold interstellar medium
astro-ph.SRB. L. Tatton, J. Th. van Loon, M. -R. Cioni, G. Clementini
Context: The details of how galaxies have evolved are imprinted in their star formation history, chemical enrichment and morpho-kinematic structure. Parameters behind these can be measured by combining photometric techniques with modelling. However, there are uncertainties from the ambiguity of colour and magnitude and the effects of interstellar reddening.
Sebastian Daemgen, Monika G. Petr-Gotzens, Serge Correia, Paula S. Teixeira
This study aims to determine the impact of stellar binary companions on the lifetime and evolution of circumstellar disks in the Chamaeleon I (Cha I) star-forming region by measuring the frequency and strength of accretion and circumstellar dust signatures around the individual components of T Tauri binary stars. We used high-angular resolution adaptive opti
Tarek Sayed Ahmed
Several open problems in algebraic logic are solved.
Tarek Sayed Ahmed
We investigate atomicity of free algebras and various forms of amalgamation for BL and MV algebras, and also Heyting algebras, though the latter algebras may not be linearly ordered, so strictly speaking their corresponding intuitionistic logic does not belong to many valued logic. Generalizing results of Comer proved in the classical first order case; worki
Luca Giomi
The shape of materials is often subject to a number of geometric constraints that limit the size of the system or fix the structure of its boundary. In soft and biological materials, however, these constraints are not always hard, but are due to other physical mechanisms that affect the overall force balance. A capillary film spanning a flexible piece of wir
Matthew G. Seetin, Wipapat Kladwang, J. P. Bida, Rhiju Das
Chemical mapping methods probe RNA structure by revealing and leveraging correlations of a nucleotide's structural accessibility or flexibility with its reactivity to various chemical probes. Pioneering work by Lucks and colleagues has expanded this method to probe hundreds of molecules at once on an Illumina sequencing platform, obviating the use of sla
G. Kucsko, P. C. Maurer, N. Y. Yao, M. Kubo
Sensitive probing of temperature variations on nanometer scales represents an outstanding challenge in many areas of modern science and technology. In particular, a thermometer capable of sub-degree temperature resolution as well as integration within a living system could provide a powerful new tool for many areas of biological research, including temperatu
Johan Bollen, David Crandall, Damion Junk, Ying Ding
Public agencies like the U.S. National Science Foundation (NSF) and the National Institutes of Health (NIH) award tens of billions of dollars in annual science funding. How can this money be distributed as efficiently as possible to best promote scientific innovation and productivity? The present system relies primarily on peer review of project proposals. I
Qi Zhou, Xiaoli Ma
Recently, lattice reduction (LR) technique has caught great attention for multi-input multi-output (MIMO) receiver because of its low complexity and high performance. However, when the number of antennas is large, LR-aided linear detectors and successive interference cancellation (SIC) detectors still exhibit considerable performance gap to the optimal maxim
V. Gupta, G. Sánchez-Colón, S. Rajpoot, H-C. Wang
We mimic the Wolfenstein scheme of quark flavor mixing to describe neutrino oscillations in the standard model. We identify the parameter $λ$ with the experimentally measured value of the mixing element responsible for atmospheric neutrino oscillations. The matrix elements responsible for solar neutrino oscillations and the Chooz angle are taken to be propor
Arlee V. Smith, Jesse J. Smith
We show by numerical modeling that saturation of the population inversion reduces the stimulated thermal Rayleigh gain relative to the laser gain in large mode area fiber amplifiers. We show how to exploit this effect to raise mode instability thresholds by a substantial factor. We also demonstrate that when suppression of stimulated Brillouin scattering and
Maciej Borodzik, Charles Livingston
We apply the methods of Heegaard Floer homology to identify topological properties of complex curves in the complex projective plane. As one application, we resolve an open conjecture that constrains the Alexander polynomial of the link of the singular point of the curve in the case that there is exactly one singular point, having connected link, and the cur
N. Javaid, M. Yaqoob, M. Y. Khan, M. A. Khan
With increase in ageing population, health care market keeps growing. There is a need for monitoring of health issues. Wireless Body Area Network (WBAN) consists of wireless sensors attached on or inside human body for monitoring vital health related problems e.g, Electro Cardiogram (ECG), Electro Encephalogram (EEG), ElectronyStagmography (ENG) etc. Due to
Eunjung Kim, Vito Rebecca, Inna V. Fedorenko, Jane L. Messina
Skin is one of the largest human organ systems whose primary purpose is the protection of deeper tissues. As such, the skin must maintain a homeostatic balance in the face of many microenvironmental and genetic perturbations. At its simplest, skin homeostasis is maintained by the balance between skin cell growth and death such that skin architecture is prese
Fabian Gundlach
We use Brauer-Manin obstructions to explain failures of the integral Hasse principle and strong approximation away from infinity for the equation x^2+y^2+z^k=m with fixed integers k>=3 and m. Under Schinzel's hypothesis (H), we prove that Brauer-Manin obstructions corresponding to specific Azumaya algebras explain all failures of strong approximation awa
Reply to the Comment on "Optimal working conditions for thermoelectric generators with realistic thermal coupling" by S. Su et al
physics.class-phY. Apertet, H. Ouerdane, O. Glavatskaya, C. Goupil
We reply to the comment made by Su et al. on "Optimal working conditions for thermoelectric generators with realistic thermal coupling". In particular we justify the efficiency definition used in the main paper.
Molybdenum, Ruthenium, and the Heavy r-process Elements in Moderately Metal-Poor Main-Sequence Turnoff Stars
astro-ph.SRRuth C. Peterson
The ratios of elemental abundances observed in metal-poor stars of the Galactic halo provide a unique present-day record of the nucleosynthesis products of its earliest stars. While the heaviest elements were synthesized by the r- and s-processes, dominant production mechanisms of light trans-ironic elements were obscure until recently. This work investigate
N. Javaid, I. Israr, M. A. Khan, A. Javaid
This paper presents comparison of Access Techniques used in Medium Access Control (MAC) protocol for Wireless Body Area Networks (WBANs). Comparison is performed between Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA), Pure ALOHA and Slotted ALOHA (S-ALOHA). Per
Ivan S. Grudinin, Guoping Lin, Nan Yu
Whispering gallery modes in birefringent crystalline resonators are investigated. We experimentally investigate the XY--cut resonators made with LiNbO$_3$, LiTaO$_3$ and BBO and observe strong influence of the resonator's shape and birefringence on the quality factor of the extraordinary polarized modes. We show that extraordinary modes can have lower Q
Rodolfo I. Meneguette, Luiz F. Bittencourt, Edmundo R. M. Madeira
Vehicular Ad Hoc Networks (VANETs) are self-organizing, self-healing networks which provide wireless communication among vehicular and roadside devices. Applications in such networks can take advantage of the use of simultaneous connections, thereby maximizing the throughput and lowering latency. In order to take advantage of all radio interfaces of the vehi
Solutions of the Pell equations x^2-(a^2+2a)y^2=N via generalized Fibonacci and Lucas numbers
math.NTBilge Peker
In this study, we find continued fraction expansion of sqrt(d) when d=a^2+2a where a is positive integer. We consider the integer solutions of the Pell equation x^2-(a^2+2a)y^2=N when N={-1,+1,-4,+4}. We formulate the n-th solution (x_{n},y_{n}) by using the continued fraction expansion. We also formulate the n-th solution (x_{n},y_{n}) via the generalized F
M. E. Brown
A recent stellar occultation by dwarf planet Makemake provided an excellent opportunity to measure the size and shape of one of the largest objects in the Kuiper belt. The analysis of these results provided what were reported to be precise measurements of the lengths of the projected axes, the albedo, and even the density of Makemake, but these results were,
A. P. L. Robinson, D. J. Strozzi, J. R. Davies, L. Gremillet
Fast Ignition Inertial Confinement Fusion is a variant of inertial fusion in which DT fuel is first compressed to high density and then ignited by a relativistic electron beam generated by a fast (< 20 ps) ultra-intense laser pulse, which is usually brought in to the dense plasma via the inclusion of a re-entrant cone. The transport of this beam from the con
Sears Merritt, Aaron Clauset
In most professional sports, the structure of the environment is kept neutral so that scoring imbalances may be attributed to differences in team skill. It thus remains unknown what impact structural heterogeneities can have on scoring dynamics and producing competitive advantages. Applying a generative model of scoring dynamics to roughly 10 million team co
Bohdan Lisnyi
The ground state and thermodynamic properties of an asymmetric diamond Ising--Hubbard chain with the on-site electron-electron attraction has been considered. The problem can be solved exactly using the decoration-iteration transformation. In the case of the antiferromagnetic Ising interaction, the influence of this attraction on the ground state and the tem
Correlation functions in liquids and crystals : Free energy functional and liquid - crystal transition
cond-mat.softAtul S. Bharadwaj, Swarn L. Singh, Yashwant Singh
A free energy functional for a crystal that contains both the symmetry conserved and symmetry broken parts of the direct pair correlation function has been used to investigate the crystallization of fluids in three-dimensions. The symmetry broken part of the direct pair correlation function has been calculated using a series in ascending powers of the order
Yuri Sachkov
We compute two vector field models of the Carnot algebra with the growth vector (2,3,5,8), and an infinitesimal symmetry of the corresponding sub-Riemannian structure.
A Fixed Point Theorem and Equilibria of Abstract Economies with w-Upper Semicontinuous Set-Valued Maps
math.OCCarlos Hervés-Beloso, Monica Patriche
We introduce the notion of w-upper semicontinuous set valued maps and give a new fixed-point theorem. We also introduce the notion of set valued maps with e-USS-property. These results can be applied to obtain some new equilibrium theorems for abstract economies.
J. Nieves, I. Ruiz Simo, F. Sánchez, M. J. Vicente Vacas
We analyze the MiniBooNE muon neutrino CCQE-like dσ/dT_μ/dcosθ_μdata using a theoretical model that, among other nuclear effects, includes RPA correlations and 2p2h (multinucleon) mechanisms. These corrections turn out to be essential for the description of the data. We find that MiniBooNE CCQE-like data are fully compatible with former determinations of the
I. Reidler, M. Nixon, Y. Aviad, S. Guberman
The synchronization of chaotic lasers and the optical phase synchronization of light originating in multiple coupled lasers have both been extensively studied, however, the interplay between these two phenomena, especially at the network level is unexplored. Here we experimentally compare chaos synchronization of laser networks with heterogeneous coupling de
Annalisa Cerquetti
Favaro, Lijoi, and Pruenster (2012, Biometrics, 68, 1188--1196) derive a novel Bayesian nonparametric estimator of the probability of detecting at the $(n+m+1)$th observation a species already observed with any given frequency in an enlarged sample of size $n+m$, conditionally on a basic sample of size $n$. Unfortunately the general result under Gibbs priors
Magnetic topology and current channels in plasmas with toroidal current density inversions
physics.plasm-phDavid Ciro, Iberê L. Caldas
The equilibrium magnetic field inside axisymmetric plasmas with inversions on the toroidal current density is studied. Structurally stable non-nested magnetic surfaces are considered. For any inversion in the internal current density the magnetic families define several positive current channels about a central negative one. A general expression relating the
V. D. Lakhno, A. N. Korshunova
A charge motion in an electric field in a Holstein molecular chain is modeled in the absence of dissipation. It is shown that in a weak electric field a Holstein polaron moves uniformly experiencing small oscillations of its shape. These oscillations are associated with the chain's discreteness and caused by the presence of Peierls-Nabarro potential ther
Steven C. Erwin, P. C. Snijders
When gold is deposited on Si(553), the surface self-assembles to form a periodic array of steps with nearly perfect structural order. In scanning tunneling microscopy these steps resemble quasi-one-dimensional atomic chains. At temperatures below ~50 K the chains develop tripled periodicity. We recently predicted, on the basis of density-functional theory ca
Sergio Venturini
Let $\MSpace$ be a locally compact metric space and let $\pMap:\MSpace\to\MSpace$ be a not expansive map. We prove that for each $\ppa_0\in\MSpace$ the sequence $\ppa_0,\pMap(\ppa_0),\pMap^2(\ppa_0),\ldots$ is either relatively compact in $\MSpace$ or compactly divergent in $\MSpace$. As applications we study the structure of the functions which are limits o
Amelia Carolina Sparavigna
The study and development of software able to show the effect of aging of faces is one of the tasks of face recognition technologies. Some software solutions are used for investigations, some others to show the effects of drugs on healthy appearance, however some other applications can be proposed for the analysis of visual arts. Here we use a freely availab
C. García-Recio, L. S. Geng, J. Nieves, L. L. Salcedo
We review and extend the model derived in Phys. Rev. D83 016007 (2011) to address the dynamics of the low-lying even parity meson resonances. This model is based on a coupled channels spin-flavor extension of the chiral Weinberg-Tomozawa Lagrangian. This interaction is then used to study the S-wave meson-meson scattering involving members not only of the π-o
Antonis G. Gotsis, Angeliki Alexiou
Wireless access through a large distributed network of low-complexity infrastructure nodes empowered with cooperation and coordination capabilities, is an emerging radio architecture, candidate to deal with the mobile data capacity crunch. In the 3GPP evolutionary path, this is known as the Cloud-RAN paradigm for future radio. In such a complex network, dist
Full-band electronic structure calculation of semiconductor nanostructures: a reduced-order approach
cond-mat.mes-hallFrancesco Bertazzi, Xiangyu Zhou, Michele Goano, Enrico Bellotti
We propose an efficient reduced-order technique for electronic structure calculations of semiconductor nanostructures, suited for inclusion in full-band quantum transport simulators. The model is based on the linear combination of bulk bands obtained by the empirical pseudopotential method, combined with the use of problem-matched basis functions numerically
Hsiang-Chih Chiu, Sedat Dogan, Mirjam Volkmann, Christian Klinke
The frictional properties of individual multiwalled boron nitride nanotubes (BN-NTs) synthesized by chemical vapor deposition (CVD) and deposited on a silicon substrate are investigated using an atomic force microscope tip sliding along (longitudinal sliding) and across (transverse sliding) the tube's principal axis. Because of the tube transverse deform
Andrea Crespi, Roberto Osellame, Roberta Ramponi, Vittorio Giovannetti
Waves fail to propagate in random media. First predicted for quantum particles in the presence of a disordered potential, Anderson localization has been observed also in classical acoustics, electromagnetism and optics. Here, for the first time, we report the observation of Anderson localization of pairs of entangled photons in a two-particle discrete quantu
Zoltán Keresztes, Mats Forsberg, Michael Bradley, Peter K. S. Dunsby
We investigate perturbations of Kantowski-Sachs models with a positive cosmological constant, using the gauge invariant 1+3 and 1+1+2 covariant splits of spacetime together with a harmonic decomposition. The perturbations are assumed to be vorticity-free and of perfect fluid type, but otherwise include general scalar, vector and tensor modes. In this case th
Reply to arXiv:1211.3957 and arXiv:1211.4731 by Leader et al. and arXiv:1212.0761 by Harindranath et al
hep-phXiangdong Ji, Xiaonu Xiong, Feng Yuan
We reply to the recent comments on our published papers, Phys. Rev. Lett. 109 (2012) 152005 and Phys. Lett. B717 (2012) 214. We point out that the criticisms about the transverse polarization parton sum rule we obtained are invalid.
Oscar Cata
A complete and systematic effective field theory analysis of new physics effects in \bar{f}f -> ZZ and \bar{f}f -> γZ is performed. Results are presented for the different initial and final-state polarized differential cross sections in terms of oblique, gauge-fermion and neutral triple gauge corrections (nTGC). Phenomenological signatures for new physics de
Mika Göös, Juho Hirvonen, Jukka Suomela
By prior work, there is a distributed algorithm that finds a maximal fractional matching (maximal edge packing) in $O(Δ)$ rounds, where $Δ$ is the maximum degree of the graph. We show that this is optimal: there is no distributed algorithm that finds a maximal fractional matching in $o(Δ)$ rounds. Our work gives the first linear-in-$Δ$ lower bound for a natu
N. V. Vinodchandran, Marius Zimand
We show that if DTIME[2^O(n)] is not included in DSPACE[2^o(n)], then, for every set B in PSPACE/poly, all strings x in B of length n can be represented by a string compressed(x) of length at most log(|B^{=n}|)+O(log n), such that a polynomial-time algorithm, given compressed(x), can distinguish x from all the other strings in B^{=n}. Modulo the O(log n) add
O. J. Katime Santrich, C. B. Pereira, N. A. Drake
Context: Open clusters are very useful targets for examining possible trends in galactocentric distance and age, especially when young and old open clusters are compared. Aims: We carried out a detailed spectroscopic analysis to derive the chemical composition of seven red giants in the young open cluster NGC 3114. Abundances of C, N, O, Li, Na, Mg, Al, Ca,
Ekaterina Pek, Ralf Lämmel
Context: Software Engineering research makes use of collections of software artifacts (corpora) to derive empirical evidence from. Goal: To improve quality and reproducibility of research, we need to understand the characteristics of used corpora. Method: For that, we perform a literature survey using grounded theory. We analyze the latest proceedings of sev
Pavel Kornilovitch, Robert Walmsley
An excitation method for MEMS devices with planar electrodes is described. The stationary part of the device (the stator) consists of three electrode arrays arranged in the 'ABCABC' order. 'A', 'B', and 'C' carry time-independent potentials and together form a spatially-periodic electrostatic profile. The moving part of the de
Wil van der Aalst
Directed graphs can be partitioned in so-called passages. A passage P is a set of edges such that any two edges sharing the same initial vertex or sharing the same terminal vertex are both inside $P$ or are both outside of P. Passages were first identified in the context of process mining where they are used to successfully decompose process discovery and co
Collisionless shocks in partly ionized plasma with cosmic rays: microphysics of non-thermal components
astro-ph.HEA. M. Bykov, M. A. Malkov, J. C. Raymond, A. M. Krassilchtchikov
In this review we discuss some observational aspects and theoretical models of astrophysical collisionless shocks in partly ionized plasma with the presence of non-thermal components. A specific feature of fast strong collisionless shocks is their ability to accelerate energetic particles that can modify the shock upstream flow and form the shock precursors.
Abderrahim Azouani, Eric Olson, Edriss S. Titi
We present a new continuous data assimilation algorithm based on ideas that have been developed for designing finite-dimensional feedback controls for dissipative dynamical systems, in particular, in the context of the incompressible two-dimensional Navier--Stokes equations. These ideas are motivated by the fact that dissipative dynamical systems possess fin
Christopher D. Cantwell, Dwight Barkley
Flow past a circular cylinder is investigated in the subcritical regime, below the onset of Benard-von Karman vortex shedding at Re_c ~ 47. The transient response of infinitesimal perturbations is computed. The domain requirements for obtaining converged results is discussed at length. It is shown that energy amplification occurs as low as Re=2.2. Throughout
Alexander Borichev, Omar El-Fallah, Abdelouahab Hanine
We use the so called resolvent transform method to study the cyclicity of the one point mass singular inner function in weighted Bergman type spaces.
Bob Yunsheng Tian, Sabine Stanley
Recent discoveries of water-rich, sub-Neptunian to Neptunian-massed exoplanets with short-period orbits present a new parameter space for the study of exoplanetary dynamos. We explore the geometry of the dynamo source region within this parameter space using 1-D interior structure models. We model planets with 4 chemically distinct layers that consist of (1)
A. S. Avanesov, V. I. Manko
The problem of classical particle in linear potential is studied by using the formalism of Hilbert space and tomographic probability distribution. The Liouville equation for this problem is solved by finding the density matrix satisfying von Newmann-like equation in the form of product of wave functions. The relation to quantum mechanics is discussed.
Lorenzo Rovigatti, Daniel de las Heras, José Maria Tavares, Margarida M. Telo da Gama
We investigate the phase behaviour of 2D mixtures of bi-functional and three-functional patchy particles and 3D mixtures of bi-functional and tetra-functional patchy particles by means of Monte Carlo simulations and Wertheim theory. We start by computing the critical points of the pure systems and then we investigate how the critical parameters change upon l
The average absorption properties of broad absorption line quasars at 800 < lambda_rest < 3000 Å, and the underlying physical parameters
astro-ph.COAlexei Baskin, Ari Laor, Fred Hamann
Broad absorption line quasars (BALQs) present a large diversity in their broad absorption line (BAL) profiles. To investigate what physical parameters underlie this diversity, we construct a sample of BALQs which covers lambda_rest ~ 800-3000 Å, based on the Sloan Digital Sky Survey DR7 quasar catalogue. The average BAL properties are evaluated by taking the
Filippo Dell'Oro, Vittorino Pata
We analyze a differential system describing a Timoshenko beam coupled with a temperature evolution of Gurtin-Pipkin type. A necessary and sufficient condition for exponential stability is established in terms of the structural parameters of the equations. In particular, we generalize previously known results on the Fourier-Timoshenko and the Cattaneo-Timoshe
N. Javaid, Q. Ain, M. A. Khan, A. Javaid
Energy efficient routing protocols are consistently cited as efficient solutions for Wireless Sensor Networks (WSNs) routing. The area of WSNs is one of the emerging and fast growing fields which brought low cost, low power and multi-functional sensor nodes. In this paper, we examine some protocols related to homogeneous and heterogeneous networks. To evalua
Antonio Cammarata, James M. Rondinelli
Negative charge transfer $AB$O$_3$ oxides may undergo electronic metal--insulator transitions (MIT) concomitant with a dilation and contraction of nearly rigid octahedra. On both sides of the MIT are in-phase or out-of-phase (or both) rotations of adjacent octahedra that buckle the $B$--O--$B$ bond angle away from 180$^\circ$. Using density functional theory
S. Ahmed, N. Javaid, S. H. Bouk, A. Javaid
As sensor nodes are deployed anywhere in a wireless sensor network, hence their communication can be easily monitored. In these networks, message protection and node identification are very issues. Hence, security of large scale such networks requires efficient key distribution and management mechanisms. Quantum cryptography and particularly quantum key dist
L. De Angelis, R. Marotta, F. Pezzella, R. Troise
In the framework of Type IIB String Theory compactified on a general six-torus T6 with arbitrary complex structure, Yukawa couplings are determined for the chiral matter described by open strings ending on D9-branes having different oblique magnetization.
Anna Nelles, Stijn Buitink, Arthur Corstanje, Emilio Enriquez
LOFAR (the Low Frequency Array) is the largest radio telescope in the world for observing low frequency radio emission from 10 to 240 MHz. In addition to its use as an interferometric array, LOFAR is now routinely used to detect cosmic ray induced air showers by their radio emission. The LOFAR core in the Netherlands has a higher density of antennas than any
Gianluca Crippa, Carlotta Donadello, Laura V. Spinolo
We establish well-posedness of initial-boundary value problems for continuity equations with BV (bounded total variation) coefficients. We do not prescribe any condition on the orientation of the coefficients at the boundary of the domain. We also discuss some examples showing that, regardless the orientation of the coefficients at the boundary, uniqueness m
László Temleitner, László Pusztai
Total scattering neutron powder diffraction measurements were performed on the tetragonal phase (a=6.4202(5) Å, c=9.5762(12) Å) of $CI_4$. The experiments were followed by Reverse Monte Carlo (for POWder diffraction (RMCPOW)) modeling. Detailed analyses of the resulting particle configurations revealed that the observed diffuse scattering originates from the
Tuning the Electronic and Optical properties of Graphene and Boron-Nitride Quantum Dots through Molecular Charge-transfer Interactions
cond-mat.mtrl-sciArkamita Bandyopadhyay, Sharma SRKC Yamijala, Swapan K Pati
Spin-polarized first-principles calculations have been performed to tune the electronic and optical properties of graphene (G) and boron-nitride (BN) quantum dots (QDs) through molecular charge-transfer using Tetracyanoquinodimethane (TCNQ) and Tetrathiafulvalene (TTF) as dopants. From our calculations, we find that the nature of interaction between the dopa
M. C. Gordillo, J. Boronat
We report diffusion Monte Carlo calculations on the phase diagrams of para-H2 and ortho-D2 adsorbed on top of a first layer of the same substances on graphene. We found that the ground state of the second layer is a triangular incommensurate solid for both isotopes. The densities for promotion to a second layer and for the onset of a two-dimensional solid on
Toward Evolution Strategies Application in Automatic Polyphonic Music Transcription using Electronic Synthesis
cs.SDHerve Kabamba Mbikayi
We present in this paper a new approach for polyphonic music transcription using evolution strategies (ES). Automatic music transcription is a complex process that still remains an open challenge. Using an audio signal to be transcribed as target for our ES, information needed to generate a MIDI file can be extracted from this latter one. Many techniques pre
Claudio Borile, Amos Maritan, Miguel A. Muñoz
We study systems with two symmetric absorbing states, such as the voter model and variations of it, which have been broadly used as minimal neutral models in genetics, population ecology, sociology, etc. We analyze the effects of a key ingredient ineluctably present in most real applications: random-field-like quenched disorder. In accord with simulations an
Stefan Lebernegg, Alexander A. Tsirlin, Oleg Janson, Helge Rosner
Magnetic susceptibility and microscopic magnetic model of the mineral clinoclase Cu3(AsO4)(OH)3 are reported. This material can be well described as a combination of two nonequivalent spin dimers with the sizable magnetic couplings of J about 700 K and J(D2) about 300 K. Based on density functional theory calculations, we pinpoint the location of dimers in t
Parametric (quasi-Cherenkov) cooperative radiation produced by electron bunches in natural or photonic crystals
physics.acc-phS. V. Anishchenko, V. G. Baryshevsky
We use numerical modeling to study the features of parametric (quasi-Cherenkov) cooperative radiation arising when an electron bunch passes through a crystal (natural or artificial) under the conditions of dynamical diffraction of electromagnetic waves in the presence of shot noise. It is shown that in both Laue and Bragg diffraction cases, parametric radiat
Gosta Grahne, Adrian Onet, Nihat Tartal
Due to the ever increasing importance of the internet, interoperability of heterogeneous data sources is as well of ever increasing importance. Interoperability can be achieved e.g. through data integration and data exchange. Common to both approaches is the need for the DBMS to be able to store and query incomplete databases. In this report we present PossD
Tarek Sayed Ahmed
We prove several representation theorems for infinitary predicate modal logic
Tomas Salac
We apply the Cartan-Kahler theorem for the k-Dirac operator studied in Clifford analysis and to the parabolic version of this operator. We show that for k = 2 the tableaux of the first prolongations of these two operators are involutive. This gives us a new characterization of the set of initial conditions for the 2-Dirac operator.
Investigation of quantum-dimensional structure parameters by X-ray optical, scanning tunneling and transmission electron microscopy
cond-mat.mtrl-sciA. G. Touryanski, V. M. Senkov, S. S. Gizha, L. V. Arapkina
Application of the two-wavelength X-ray reflectometry to exploration of Ge/Si(001) hereostructures with dense chains of stacked Ge quantum dots is presented
Revealing the Complex Transport Behaviors in Warm Dense Hydrogen by Including Nuclear Quantum Effects
cond-mat.mtrl-sciDongdong Kang, Huayang Sun, Jiayu Dai, Zengxiu Zhao
Nuclear quantum effects (NQEs) on the structures and transport properties of dense liquid hydrogen at densities of 10-100 g/cm3 and temperatures of 0.1-1 eV are fully assessed using \textit{ab initio} path-integral molecular dynamics simulations. With the inclusion of NQEs, ionic diffusions are strongly enhanced by the magnitude from 100% to 15% with increas
Julia Heinl, Martin Schneider, Piet W. Brouwer
We study the influence of a magnetic flux tube on the possibility to electrostatically confine electrons in a graphene quantum dot. Without magnetic flux tube, the graphene pseudospin is responsible for a quantization of the total angular momentum to half-integer values. On the other hand, with a flux tube containing half a flux quantum, the Aharonov-Bohm ph
Mihai Putinar, Claus Scheiderer
Let I be a conjugation-invariant ideal in the complex polynomial ring with variables z_1,...,z_n and their conjugates. The ideal I has the Quillen property if every real valued, strictly positive polynomial on the real zero set of I in C^n is a sum of hermitian squares modulo I. We first relate the Quillen property to the archimedean property from real algeb
Yang Wang, Avi Gozolchiani, Yosef Ashkenazy, Yehiel Berezin
The connectivity pattern of networks, which are based on a correlation between ground level temperature time series, shows a dominant dense stripe of links in the southern ocean. We show that statistical categorization of these links yields a clear association with the pattern of an atmospheric Rossby wave, one of the major mechanisms associated with the wea
Clément Marteau, Peter Mathé
The authors discuss how general regularization schemes, in particular linear regularization schemes and projection schemes, can be used to design tests for signal detection in statistical inverse problems. It is shown that such tests can attain the minimax separation rates when the regularization parameter is chosen appropriately. It is also shown how to mod
Joël Bensoam
Although acoustics is one of the disciplines of mechanics, its "geometrization" is still limited to a few areas. As shown in the work on nonlinear propagation in Reissner beams, it seems that an interpretation of the theories of acoustics through the concepts of differential geometry can help to address the non-linear phenomena in their intrinsic qua
Topology across the finite temperature transition studied by overimproved cooling in gluodynamics and QCD
hep-latV. G. Bornyakov, E. -M. Ilgenfritz, B. V. Martemyanov, V. K. Mitrjushkin
Gluodynamics and two-flavor QCD at non-zero temperature are studied with the so-called overimproved cooling technique under which caloron solutions may remain stable. We consider topological configurations either at the first occuring stable plateau of topological charge or at the first (anti)selfdual plateau and find the corresponding topological susceptibi
Topologically protected quantum transport in locally exfoliated bismuth at room temperature
cond-mat.mes-hallC. Sabater, D. Gosálbez-Martínez, J. Fernández-Rossier, J. G. Rodrigo
We report electrical conductance measurements of Bi nanocontacts created by repeated tip-surface indentation using a scanning tunneling microscope at temperatures of 4 K and 300 K. As a function of the elongation of the nanocontact we measure robust, tens of nanometers long plateaus of conductance G0 = 2e^2/h at room temperature. This observation can be acco
Stefano Bosia, Stefania Gatti
We consider a model for the evolution of a mixture of two incompressible and partially immiscible Newtonian fluids in two dimensional bounded domain. More precisely, we address the well-known model H consisting of the Navier-Stokes equation with non-autonomous external forcing term for the (average) fluid velocity, coupled with a convective Cahn-Hilliard equ
Three dimensional complex plasma structures in a combined radio frequency and direct current discharge
physics.plasm-phS. Mitic, B. A. Klumov, S. A. Khrapak, G. E. Morfill
We report on the first detailed analysis of large three dimensional (3D) complex plasma structures in experiments performed in pure rf and combined rf+dc discharge modes. Inductively coupled plasma (ICP) is generated by an rf coil wrapped around the vertically positioned cylindrical glass tube at a pressure of 0.3 mbar. In addition, dc plasma can be generate
Alexander S. Gusev, Svetlana A. Guslyakova, Maria S. Khramtsova
We have analyzed the radial scales, central surface brightnesses, and colors of 404 disks of various types of galaxies. The central surface brightness mu0 and linear disk scale length h vary smoothly along the Hubble sequence of galaxies within a rather narrow interval. The disks of relatively early type galaxies display higher central surface brightnesses i
L'-band AGPM vector vortex coronagraph's first light on VLT/NACO: Discovery of a late-type companion at two beamwidths from an F0V star
astro-ph.IMD. Mawet, O. Absil, C. Delacroix, J. H. Girard
Context. High contrast imaging has thoroughly combed through the limited search space accessible with first-generation ground-based adaptive optics instruments and the Hubble Space Telescope. Only a few objects were discovered, and many non-detections reported and statistically interpreted. The field is now in need of a technological breakthrough. Aim. Our a
T. Rauscher, C. Fröhlich
Although the detailed conditions for explosive nucleosynthesis are derived from astrophysical modeling, nuclear physics determines fundamental patterns in abundance yields, not only for equilibrium processes. Focussing on the nu-p- and the gamma-process, general nucleosynthesis features within the range of astrophysical models, but (mostly) independent of de
V. A. Sadovnikova
In the theory of the finite fermi-systems [1], it was shown that giant resonances in nuclei can be consider as the zero-sound excitations which exhaust the large part of the energy-weighted sum rules. In the framework of [1] the solutions of the zero-sound dispersion equation in the symmetric nuclear matter, ω_s(k), are considered. The method of calculation
Julie Forman, Michael Sørensen
This article demonstrates that flexible and statistically tractable multi-modal diffusion models can be attained by transformation of simple well-known diffusion models such as the Ornstein-Uhlenbeck model, or more generally a Pearson diffusion. The transformed diffusion inherits many properties of the underlying simple diffusion including its mixing rates a
Marc Joyeux, Jocelyne Vreede
The Histone-like Nucleoid Structuring protein (H-NS) is a nucleoid-associated protein, which is involved in both gene regulation and DNA compaction. H-NS can bind to DNA in two different ways: in trans, by binding to two separate DNA duplexes, or in cis, by binding to different sites on the same duplex. Based on scanning force microscopy imaging and optical
N. Yu. Agafonova, A. S. Malgin
The experimental data on the yield of muon-induced neutrons for liquid scintillator, iron and lead accumulated during 60 years of muon interaction underground study have been analyzed. A universal formula connecting the yield with muon energy loss in the matter and neutron production in hadronic and electromagnetic showers is presented.
Ievgen Vovk, Andrii Neronov
We investigate the variability properties of blazars in the GeV band using the data of the Fermi/LAT telescope. We find that blazars exhibit variability on the scales down to the minimal timescale resolvable by Fermi, which is a function of the peak photon count rate in the LAT. This implies that the real minimal variability timescales for the majority of bl
A. Lamura, G. Gompper
The dynamics and rheology of suspensions of fluid vesicles or red blood cells is investigated by a combination of molecular dynamics and mesoscale hydrodynamics simulations in two dimensions. The vesicle suspension is confined between two no-slip walls, which are driven externally to generate a shear flow with shear rate $\dotγ$. The flow behavior is studied