January 2013 arXiv papers — page 5

Ivan Duchemin, Xavier Blase

We study within the many-body Green's function GW and Bethe-Salpeter approaches the neutral singlet excitations of the zinctetraphenylporphyrin and C70 fullerene donor-acceptor complex. The lowest transition is a charge-transfer excitation between the donor and the acceptor with an energy in excellent agreement with recent constrained density functional

Qi-Hui Chen, Long-Fei Guo, Peng Li

We study the dimer $XXZ$ spin model on two-leg ladders with isotropic Heisenberg interactions on the rung and anisotropic $XXZ$ interactions along the rail in an external field. Combining both analytical and numerical methods, we set up the ground state phase diagram and investigate the quantum phase transitions and the properties of rich phases, including t

A. M. Baldini, F. Cei, C. Cerri, S. Dussoni

We propose the continuation of the MEG experiment to search for the charged lepton flavour violating decay (cLFV) μ\to e γ, based on an upgrade of the experiment, which aims for a sensitivity enhancement of one order of magnitude compared to the final MEG result, down to the $6 \times 10^{-14}$ level. The key features of this new MEG upgrade are an increased

Michal Sumbera

Results from the Beam Energy Scan (BES) program conducted recently by STAR experiment at RHIC are presented. The data from Phase-I of the BES program collected in Au+Au collisions at center-of-mass energies (\sqrt{s_{NN}}) of 7.7, 11.5, 19.6, 27, and 39 GeV cover a wide range of baryon chemical potential ?μ_B (100-400 MeV) in the QCD phase diagram. Several S

Sara Arklint, Rasmus Bentmann, Takeshi Katsura

We show that filtered K-theory is equivalent to a substantially smaller invariant for all real-rank-zero C*-algebras with certain primitive ideal spaces -- including the infinitely many so-called accordion spaces for which filtered K-theory is known to be a complete invariant. As a consequence, we give a characterization of purely infinite Cuntz-Krieger alge

Taha Sochi, P. J. Storey

Resonances, which are also described as autoionizing or quasi-bound states, play an important role in the scattering of atoms and ions with electrons. The current article is an overview of the main methods, including a recently-proposed one, that are used to find and analyze resonances.

Rafael Hernandez, Juan Miguel Nieto

We consider the ratio of the correlation function of an hexagon light-like Wilson loop with one local operator over the expectation value of the Wilson loop within the strong-coupling regime of the AdS/CFT correspondence. We choose the hexagon Wilson loop within a class of minimal solutions obtained by cutting and gluing light-like quadrangle loops. These su

Alexander Malyshev, Galina Isupova

The transport properties of a circular billiard with attached channels, which is an open system, have been studied in the presence of the Dresselhaus and Rashba spin-orbit interactions. It has been shown that this interaction leads to the appearance of additional Fano resonances in the energy dependence of the conductance, the width of which is proportional

Takahiro Matsushita

In this paper, we introduce the notions of $r$-fundamental groups of graphs, $r$-covering maps, and $r$-neighborhood complexes of graphs for a positive integer $r$. There is a natural correspondence between $r$-covering maps and $r$-fundamental groups as is the case of the covering space theory in topology. We can derive obstructions of the existences of gra

M. Domokos

Conjugation covariants of matrices are applied to study the real algebraic variety consisting of complex Hermitian matrices with a bounded number of distinct eigenvalues. A minimal generating system of the vanishing ideal of degenerate three by three Hermitian matrices is given, and the structure of the corresponding coordinate ring as a module over the spec

Absos Ali Shaikh, Haradhan Kundu

In the literature we see that after introducing a geometric structure by imposing some restrictions on Riemann-Christoffel curvature tensor, the same type structure given by imposing same restriction on other curvature tensors being studied. The main object of the present paper is to study the equivalency of various geometric structures obtained by same rest

N. V. Sarlis, P. V. Varotsos, E. S. Skordas

Upon employing a natural time window of fixed length sliding through a time series, an explicit interrelation between the variability $β$ of the variance $κ_1$($=< χ^2 > - < χ>^2$) of natural time $χ$ and events&#39; correlations is obtained. In addition, we investigate the application of the fluctuation theorem, which is a general result for systems far fro

Vesa Julin, Giovanni Pisante

We consider a non local isoperimetric problem arising as the sharp interface limit of the Ohta-Kawasaki free energy introduced to model microphase separation of diblock copolymers. We perform a second order variational analysis that allows us to provide a quantitative second order minimality condition. We show that critical configurations with positive secon

Klaus Frick, Axel Munk, Hannes Sieling

We introduce a new estimator SMUCE (simultaneous multiscale change-point estimator) for the change-point problem in exponential family regression. An unknown step function is estimated by minimizing the number of change-points over the acceptance region of a multiscale test at a level α. The probability of overestimating the true number of change-points K is

Boris Dubrovin, Andrei Kapaev

We show that the fourth order nonlinear ODE which controls the pole dynamics in the general solution of equation $P_I^2$ compatible with the KdV equation exhibits two remarkable properties: 1) it governs the isomonodromy deformations of a $2\times2$ matrix linear ODE with polynomial coefficients, and 2) it does not possesses the Painlevé property. We also st

R. V. Bessonov

We generalize a classical result by A.Macintyre and W.Rogosinski on best $H^p$--approximation in $L^p$ of rational functions. For each inner function $θ$ we give a description of $H^p$--badly approximable functions in $\bar θH^p$.

Ippei Kishida, Kengo Orita, Atsutomo Nakamura, Yoshiyuki Yokogawa

LiNi0.5Mn1.5O4, which has a spinel framework structure, is a promising candidate for the cathode material of next-generation lithium-ion batteries with high energy density. We investigate the structural transition in LixNi0.5Mn1.5O4 (0 <= x <= 1) through first-principles calculations using the projector augmented wave method with the generalized gradient app

Maksym Teslyk, Olena Teslyk

We consider scalar field entanglement entropy generated with black hole of (sub)planck mass scale thus implying the unitary evolution of gravity. The dependence on the dimension of the Hilbert space for degrees of freedom located behind the horizon is taken into account. The obtained results contain polylogarithmic terms.

V. K. Shchigolev

We propose a new type of cosmological model derived from the fractional variational principle when it is applied to the gravitational sector of action functional. In contrast to the fractional cosmological model developed earlier by the author from a fractional total action, in our new model the continuity equation remains valid in its usual form. For this m

V. Čekanavičius, P. Vellaisamy

Sums of of 1-dependent integer-valued random variables are approximated by compound Poisson, negative binomial and Binomial distributions and signed compound Poisson measures. Estimates are obtained for total variation and local metrics. The results are then applied to statistics of $m$-dependent $(k_1,k_2)$ events and 2-runs. Heinrich&#39;s method and smoot

Meili Guo, Jiulin Du

Electronic structures and optical properties of C-N-codoped anatase TiO2 were calculated by using GGA+U method based on the density functional theory. The calculated results showed that the N-doped, C-doped, and C-N-codoped TiO2 produced 2p states in band gap, and the band gaps of the three doped systems decreased compared with the pure TiO2. According to th

Felix Just, Andrea Cavanna, Maria V. Chekhova, Gerd Leuchs

We measure the transverse entanglement of photon pairs on their propagation from the near to the far field of spontaneous parametric downconversion (SPDC). The Fedorov ratio, depending on the widths of conditional and unconditional intensity measurements, is shown to be only able to characterize entanglement in the near and far field zones of the source. The

Toni Heikkinen, Juha Lehrbäck, Juho Nuutinen, Heli Tuominen

We study the mapping properties of fractional maximal operators in Sobolev and Campanato spaces in metric measure spaces. We show that, under certain restrictions on the underlying metric measure space, fractional maximal operators improve the Sobolev regularity of functions and map functions in Campanato spaces to Hölder continuous functions. We also give a

Jose M. Peña

In Peña (2007), MCMC sampling is applied to approximately calculate the ratio of essential graphs (EGs) to directed acyclic graphs (DAGs) for up to 20 nodes. In the present paper, we extend that work from 20 to 31 nodes. We also extend that work by computing the approximate ratio of connected EGs to connected DAGs, of connected EGs to EGs, and of connected D

Matthew Levy

It has been shown by Lubotzky in [10] that the set of verbal images of a fixed non-abelian finite simple group G is precisely the set of endomorphism invariant subsets of G. Here we use his result to determine the verbal images of certain almost simple groups and quasisimple groups.

Enrico Pajer, Matias Zaldarriaga

Standard perturbation theory (SPT) for large-scale matter inhomogeneities is unsatisfactory for at least three reasons: there is no clear expansion parameter since the density contrast is not small on all scales; it does not fully account for deviations at large scales from a perfect pressureless fluid induced by short-scale non-linearities; for generic init

Attila Bérczes, Jan-Hendrik Evertse, Kálmán Györy

Let A be an arbitrary integral domain of characteristic 0 which is finitely generated over Z. We consider Thue equations $F(x,y)=b$ with unknowns x,y from A and hyper- and superelliptic equations $f(x)=by^m$ with unknowns from A, where the binary form F and the polynomial f have their coefficients in A, where b is a non-zero element from A, and where m is an

Attila Bérczes, Jan-Hendrik Evertse, Kálmán Györy

We consider hyper- and superelliptic equations $f(x)=by^m$ with unknowns x,y from the ring of S-integers of a given number field K. Here, f is a polynomial with S-integral coefficients of degree n with non-zero discriminant and b is a non-zero S-integer. Assuming that n>2 if m=2 or n>1 if m>2, we give completely explicit upper bounds for the heights of the s

Anupam Pal Choudhury

In this article, we discuss about the resolution of the Riemann problem for a 2x2 system in nonconservative form exhibiting parabolic degeneracy. The system can be perceived as the limiting equation (depending on a parameter tending to 0) of a 2x2 strictly hyperbolic, genuinely nonlinear, non-conservative system arising in context of a model in elastodynamic

Matthew Kahle

This expository article is based on a lecture from the Stanford Symposium on Algebraic Topology: Application and New Directions, held in honor of Gunnar Carlsson, Ralph Cohen, and Ib Madsen.

Richard Lockhart, Jonathan Taylor, Ryan J. Tibshirani, Robert Tibshirani

In the sparse linear regression setting, we consider testing the significance of the predictor variable that enters the current lasso model, in the sequence of models visited along the lasso solution path. We propose a simple test statistic based on lasso fitted values, called the covariance test statistic, and show that when the true model is linear, this s

Atsunori Sakurai, Yoshitaka Tanimura

The quantum dissipative dynamics of a tunneling process through double barrier structures is investigated on the basis of a rigorous treatment for the first time. We employ a Caldeira-Leggett Hamiltonian with an effective potential calculated self-consistently, accounting for the electron distribution. With this Hamiltonian, we use the reduced hierarchy equa

Hector Aceves, F. J. Tamayo, L. Altamirano-Devora, F. G. Ramon-Fox

We study the distribution of intragroup dark matter in small groups of dark matter halos of galaxy-like size in a LCDM cosmology. These groups are identified using a physical criterion and may be an appropriate representation of small galaxy groups. We quantify the amount of intragroup dark matter and characterize its distribution. We find that compact assoc

Marc Arnaudon, Laurent Miclo

A stochastic algorithm is proposed, finding some elements from the set of intrinsic $p$-mean(s) associated to a probability measure $ν$ on a compact Riemannian manifold and to $p\in[1,\infty)$. It is fed sequentially with independent random variables $(Y_n)_{n\in \mathbb{N}}$ distributed according to $ν$, which is often the only available knowledge of $ν$. F

Karl Bringmann

Klee&#39;s Measure Problem (KMP) asks for the volume of the union of n axis-aligned boxes in d-space. Omitting logarithmic factors, the best algorithm has runtime O*(n^{d/2}) [Overmars,Yap&#39;91]. There are faster algorithms known for several special cases: Cube-KMP (where all boxes are cubes), Unitcube-KMP (where all boxes are cubes of equal side length),

Hisashi Naito, Hajime Urakawa

For the reduction ordinary differential equation due to Baird and Kamissoko \cite{BK} for biharmonic maps from a Riemannian manifold $(M^m,g)$ into another one $(N^n,h)$, we show that this ODE has no global positive solution for every $m\geq 5$. On the contrary, we show that there exist global positive solutions in the case $m=3$. As applications, for the th

D. P. Snowden-Ifft, J. -L. Gauvreau

High precision measurements were made of reduced mobility, lateral and longitudinal diffusion of CS2- negative ions in 40 Torr CS2 and a 30 - 10 Torr CS2 - CF4 gas mixture. The reduced mobility was found to be 353.0 +/- 0.5 cm^2 Torr / s V in CS2 and 397.4 +/- 0.7 cm^2 Torr / s V in the CS2 - CF4 gas mixture at STP. The lateral diffusion temperatures for the

Arthemy V. Kiselev, Andrey O. Krutov

We generalise to the $\mathbb{Z}_2$-graded set-up a practical method for inspecting the (non)removability of parameters in zero-curvature representations for partial differential equations (PDEs) under the action of smooth families of gauge transformations. We illustrate the generation and elimination of parameters in the flat structures over $\mathbb{Z}_2$-

G. Papadimitriou, J. Rotureau, N. Michel, M. Płoszajczak

No-Core Gamow Shell Model (NCGSM) is applied for the first time to study selected well-bound and unbound states of helium isotopes. This model is formulated on the complex energy plane and, by using a complete Berggren ensemble, treats bound, resonant, and scattering states on equal footing. We use the Density Matrix Renormalization Group method to solve the

T. Espinosa-Ortega, I. A. Luk&#39;yanchuk, Y. G. Rubo

Using the tight-binding approximation we calculated the magnetic susceptibility of graphene quantum dots (GQD) of different geometrical shapes and sizes, smaller than the magnetic length, when the magnetic properties are governed by the electron edge states. Two types of edge states can be discerned: the zero-energy states (ZES) located exactly at the zero-e

Weikang Fan, Miao Yin, Ze Cheng

The dynamic Stark shift of a high-lying atom in a system of Bose Einstein condensation (BEC) of photons is discussed within the framework of nonrelativistic quantum electrodynamics (QED) theory. It is found that the Stark shift of an atom in BEC of photons is modified by a temperature dependent factor, compared to that in a normal two-dimensional photonic fl

Peng Guo, Wenming Chen, Yi Wang

In this article, we study a single-machine scheduling problem of minimizing the total tardiness for a set of independent jobs. The processing time of a job is modeled as a step function of its starting time and a specific deteriorating date. A mixed integer programming model was applied to the problem and validated. Since the problem is known to be NP-hard,

Mathias Brucherseifer, Fabrizio Caola, Kirill Melnikov

We describe a calculation of the fully-differential decay rate of a top quark to a massless $b$-quark and a lepton pair at next-to-next-to-leading order in perturbative QCD. Technical details of the calculation are discussed and selected results for kinematic distributions are shown.

Shivani Gupta, Anjan S. Joshipura, Ketan M. Patel

Viability of the μ-τinterchange symmetry imposed as an approximate symmetry (1) on the neutrino mass matrix {\cal M}_{νf} in the flavour basis (2) simultaneously on the charged lepton mass matrix M_l and the neutrino mass matrix M_νand (3) on the underlying Lagrangian is discussed in the light of recent observation of a non-zero reactor mixing angle θ_{13}.

Y. Hori

Mixed harmonic charge dependent azimuthal correlations at mid-rapidity in Pb-Pb collisions at \sqrt{s_{NN}} = 2.76 TeV were measured with the ALICE detector at the LHC. A clear charge dependence for a series of correlations is observed both via the multi-particle cumulant and the event plane methods. Implications from these measurements for the possible effe

Changjun Gao, You-Gen Shen

By using of the Euler-Lagrange equations, we find a static spherically symmetric solution in the Einstein-aether theory with the coupling constants restricted. The solution is similar to the Reissner-Nordstrom solution in that it has an inner Cauchy horizon and an outer black hole event horizon. But a remarkable difference from the Reissner-Nordstrom solutio

Chengchun Hao

In this paper, we establish a priori estimates for the three-dimensional compressible Euler equations with moving physical vacuum boundary, the $γ$-gas law equation of state for $γ=2$ and the general initial density $\ri \in H^5$. Because of the degeneracy of the initial density, we investigate the estimates of the horizontal spatial and time derivatives and

Yoann Dieudonné, Andrzej Pelc, Vincent Villain

Two mobile agents starting at different nodes of an unknown network have to meet. This task is known in the literature as rendezvous. Each agent has a different label which is a positive integer known to it, but unknown to the other agent. Agents move in an asynchronous way: the speed of agents may vary and is controlled by an adversary. The cost of a rendez

Alexander Akulshin, Christopher Perrella, Gar-Wing Truong, Andre Luiten

We present a study of the spectral linewidth of collimated blue light (CBL) that results from wave mixing of low-power cw laser radiation at 780 nm and 776 nm and an internally-generated mid-IR field at 5.23 um in Rb vapour. Using a high-finesse Fabry-Perot interferometer the spectral width of the CBL is found to be less than 1.3 MHz for a wide range of expe

Ben Blum-Smith, Samuel Coskey

We describe the Fundamental Theorem on Symmetric Polynomials (FTSP), exposit a classical proof, and offer a novel proof that arose out of an informal course on group theory. The paper develops this proof in tandem with the pedagogical context that led to it. We also discuss the role of the FTSP both as a lemma in the original historical development of Galois

S. Campbell, L. Mazzola, G. De Chiara, T. J. G Apollaro

We perform an extensive study of the properties of global quantum correlations in finite-size one-dimensional quantum spin models at finite temperature. By adopting a recently proposed measure for global quantum correlations [C. C. Rulli, and M. S. Sarandy, Phys. Rev. A, 84, 042109 (2011)], called global discord, we show that critical points can be neatly de

Marcelo de Almeida, Mile Gu, Alessandro Fedrizzi, Matthew A. Broome

Not all quantum protocols require entanglement to outperform their classical alternatives. The nonclassical correlations that lead to this quantum advantage are conjectured to be captured by quantum discord. Here we demonstrate that discord can be explicitly used as a resource: certifying untrusted entangling gates without generating entanglement at any stag

J. X. Zheng-Johansson

Since its discovery by Max Planck in 1900, the Planck constant $h$ has been demonstrated to be an universal constant, and its numerical value has been accurately determined based on experiments. Up to the present however the physical origin of this fundamental constant has not been well understood, and the numerical value of it has not been {\it ab initio} p

H. R. Reiss

Although gauge invariance preserves the values of physical observables, a gauge transformation can introduce important alterations of physical interpretations. To understand this, it is first shown that a gauge transformation is not, in general, a unitary transformation. Also, physical interpretations are based on both kinetic energy and potential energy exp

Zhongbo Yan, Xiaosen Yang, Shaolong Wan

We study the Bose-Einstein condensate in a honeycomb optical lattice within Bogoliubov theory and find that for a ${\bf k} = 0$ condensate, the Dirac points appear in the Bogoliubov excitation spectrum when $0 < β< 2$, which illustrates that the bose-bose interaction does not change the Dirac point structure but only give a modification of the velocity of th

Scott W. McIntosh, Robert J. Leamon, Joseph B. Gurman, Jean-Philippe Olive

Among many other measurable quantities the summer of 2009 saw a considerable low in the radiative output of the Sun that was temporally coincident with the largest cosmic ray flux ever measured at 1AU. A hemispheric asymmetry in magnetic activity is clearly observed and its evolution monitored and the resulting (prolonged) magnetic imbalance must have had a

Nicolò Michelusi, Petar Popovski, Osvaldo Simeone, Marco Levorato

This paper introduces a novel technique for access by a cognitive Secondary User (SU) using best-effort transmission to a spectrum with an incumbent Primary User (PU), which uses Type-I Hybrid ARQ. The technique leverages the primary ARQ protocol to perform Interference Cancellation (IC) at the SU receiver (SUrx). Two IC mechanisms that work in concert are i

Everton M. C. Abreu, Vahid Nikoofard

Anomalies are one essential concept for the renormalization of noncommutative (NC) gauge theories. A NC space can be visualized as a deformation of the usual spacetime with the $\star$-product and can be constructed after the quantization of a given space with its symplectic structure. The Seiberg-Witten (SW) map connects NC fields, transformations parameter

Z. P. Yin, G. Kotliar

We design, from first principles calculations, a novel family of thallium halide-based compounds as candidates for new high temperature superconductors, whose superconductivity is mediated by the recently proposed mechanism of non-local correlation-enhanced strong electron-phonon coupling. Two prototype compounds namely CsTlF$_3$ and CsTlCl$_3$ are studied w

M. K. Olsen, J. F. Corney

Two Kerr-squeezed optical beams can be combined in a beamsplitter to produce non-Gaussian continuous-variable entangled states. We characterize the non-Gaussian nature of the output by calculating the third-order cumulant of quadrature variables, and predict the level of entanglement that could be generated by evaluating the Duan-Simon and Reid Einstein-Podo

Tomohide Terasoma

Francis Brown used a certain evaluation formula for multiple zeta values proved by Zagier to prove the injectivity of the homomorphism from the Motivic Galois group to the automorphism of fundamental group of projective line deleted three points. In this paper, we prove that any associators satisfies this relation. As a consequence, this relation holds for m

David F. Klosik, Stefan Bornholdt

For several decades, a leading paradigm of how to quantitatively assess scientific research has been the analysis of the aggregated citation information in a set of scientific publications. Although the representation of this information as a citation network has already been coined in the 1960s, it needed the systematic indexing of scientific literature to

Graciela Matrajt, George Flynn, Don Brownlee, Dave Joswiak

We analyzed 2 ultra-carbonaceous interplanetary dust particles and 2 cometary Wild 2 particles with infrared spectroscopy. We characterized the carrier of the 3.4 micron band in these samples and compared its profile and the CH2/CH3 ratios to the 3.4 micron band in the diffuse interstellar medium (DISM), in the insoluble organic matter (IOM) from 3 primitive

Matthew D. Blair, Christopher D. Sogge

We extend a result of the second author \cite[Theorem 1.1]{soggekaknik} to dimensions $d \geq 3$ which relates the size of $L^p$-norms of eigenfunctions for $2<p<\frac{2(d+1)}{d-1}$ to the amount of $L^2$-mass in shrinking tubes about unit-length geodesics. The proof uses bilinear oscillatory integral estimates of Lee \cite{leebilinear} and a variable coeffi

K. Hebeler, R. J. Furnstahl

We present the first results for the neutron matter equation of state (EOS) using nucleon-nucleon and three-nucleon chiral effective field theory interactions that are consistently evolved in the framework of the Similarity Renormalization Group (SRG). The dependence of the EOS on the SRG resolution scale is greatly reduced when induced three-nucleon forces

Jorge Pullin, Parampreet Singh

We summarize the talks presented at the QG4 session (loop quantum gravity: cosmology and black holes) of the 13th Marcel Grossmann Meeting held in Stockholm, Sweden.

Eyad Alkassar, Sascha Böhme, Kurt Mehlhorn, Christine Rizkallah

Formal verification of complex algorithms is challenging. Verifying their implementations goes beyond the state of the art of current automatic verification tools and usually involves intricate mathematical theorems. Certifying algorithms compute in addition to each output a witness certifying that the output is correct. A checker for such a witness is usual

G. Granger, D. Taubert, C. E. Young, L. Gaudreau

Spin qubits have been successfully realized in electrostatically defined, lateral few-electron quantum dot circuits. Qubit readout typically involves spin to charge information conversion, followed by a charge measurement made using a nearby biased quantum point contact. It is critical to understand the back-action disturbances resulting from such a measurem

G. Kazakevich, G. Flanagan, R. P. Johnson, M. Neubauer

An 805 MHz RF pillbox cavity has been designed and constructed to investigate potential muon beam acceleration and cooling techniques for a Muon Collider or Neutrino Factory. The cavity can operate in vacuum or under pressure to 100 atmospheres, at room temperature or in a liquid nitrogen bath at 77 K. The cavity has been designed for easy assembly and disas

M. Popovic, G. Flanagan, R. P. Johnson, J. H. Nipper

Modern ion accelerators and ion implantation systems need very short, highly versatile, Low Energy Beam Transport (LEBT) systems. The need for reliable and continuous operation requires LEBT designs to be simple and robust. The energy efficiency of available high temperature superconductors (HTS), with efficient and simple cryocooler refrigeration, is an add

Madhur Srivastava

The paper explains and emphasizes the need to include mandatory Intellectual Property (IP) courses in the undergraduate and graduate curriculum of STEM students. It prescribes the proposed content of IP to be covered at undergraduate level, and graduate depending on the degree pursued by the STEM student. More importantly, this paper advocates for an Integra

Aristides Gionis, Evimaria Terzi, Panayiotis Tsaparas

The process of opinion formation through synthesis and contrast of different viewpoints has been the subject of many studies in economics and social sciences. Today, this process manifests itself also in online social networks and social media. The key characteristic of successful promotion campaigns is that they take into consideration such opinion-formatio

Andrey Beresnyak, Hao Xu, Hui Li, Reinhard Schlickeiser

Cosmological MHD simulations of galaxy cluster formation show a significant amplification of seed magnetic fields. We developed a novel method to decompose cluster magnetized turbulence into modes and showed that the fraction of the fast mode is fairly large, around 1/4 in terms of energy. This is larger than that was estimated before, which implies that clu

Michel Destrade, Ray W. Ogden

Consider the constitutive law for an isotropic elastic solid with the strain-energy function expanded up to the fourth order in the strain, and the stress up to the third order in the strain. The stress-strain relation can then be inverted to give the strain in terms of the stress with a view to considering the incompressible limit. For this purpose, use of

Y. Alexahin, E. Gianfelice-Wendt, W Marsh, K. Triplett

Tune identification - i.e. attribution of the spectral peak to a particular normal mode of oscillations - can present a significant difficulty in the presence of strong transverse coupling when the normal mode with a lower damping rate dominates spectra of Turn-by-Turn oscillations in both planes. The introduced earlier phased sum algorithm helped to recover

Naoki Shioji, Marco Squassina

We provide a symmetry result for n-mode positive solutions of a general class of semi-linear elliptic systems under cooperative conditions on the nonlinearities. Moreover, we apply the result to a class of Hénon systems and provide the existence of multiple n-mode positive solutions.

Jinwoo Hwang, Junwoo Son, Jack Y. Zhang, Anderson Janotti

NiO6 octahedral tilts in the LaNiO3/SrTiO3 superlattices are quantified using position averaged convergent beam electron diffraction in scanning transmission electron microscopy. It is shown that maintaining oxygen octahedra connectivity across the interface controls the octahedral tilts in the LaNiO3 layers, their lattice parameters and their transport prop

D. J. Scott, D. Capista, I. Kourbanis, K. Seiya

During Nova operations it is planned to run the Fermilab Recycler in a 12 batch slip stacking mode. In preparation for this, measurements of the tune during a six batch injection and then as the beam is slipped by changing the RF frequency, but without a 7th injection, have been carried out in the Main Injector. The coherent tune shifts due to the changing b

D. J. Scott, D. Capista, B. Chase, J. Dye

For Project X, it is planned to inject a beam of 3 10**11 particles per bunch into the Main Injector. To prepare for this by studying the effects of higher intensity bunches in the Main Injector it is necessary to perform coalescing at 8 GeV. The results of a series of experiments and simulations of 8 GeV coalescing are presented. To increase the coalescing

H. -T. Ding, A. Francis, O. Kaczmarek, F. Karsch

We present new lattice results on the continuum extrapolation of the vector current correlation function. Lattice calculations have been carried out in the deconfined phase at a temperature of 1.1 Tc, extending our previous results at 1.45 Tc, utilizing quenched non-perturbatively clover-improved Wilson fermions and light quark masses. A systematic analysis

Shu Lin, Robert D. Pisarski, Vladimir V. Skokov

Using a matrix model, we model the deconfining phase transition at nonzero temperature for a SU(N) gauge theory at large $N$. At infinite $N$ the matrix model exhibits a Gross-Witten-Wadia transition. We show that as a consequence, both the order-disorder and the order-order interface tensions vanish identically at the critical temperature $T_d$. We estimate

Brad Hansen, Norm Murray

We present a Monte Carlo model for the structure of low mass (total mass < 25 earth mass) planetary systems that form by the in situ gravitational assembly of planetary embryos into final planets. Our model includes distributions of mass, eccentricity, inclination and period spacing that are based on the simulation of a disk of 20 earth masses, forming plane

Soumya Bera, Serge Florens, Harold Baranger, Nicolas Roch

The coupling of a qubit to a macroscopic reservoir plays a fundamental role in understanding the complex transition from the quantum to the classical world. Considering a harmonic environment, we use both intuitive arguments and numerical many-body quantum tomography to study the structure of the complete wavefunction arising in the strong-coupling regime, r

L. D. Matthews, T. Le Bertre, E. Gerard, M. C. Johnson

We present an imaging study of a sample of eight asymptotic giant branch (AGB) stars in the HI 21-cm line. Using observations from the Very Large Array, we have unambiguously detected HI emission associated with the extended circumstellar envelopes of six of the targets. The detected HI masses range from M_HI ~ 0.015-0.055 M_sun. The HI morphologies and kine

James Wurster, Rob J. Thacker

A recent approach to simulating localized feedback from active galactic nuclei by Power et al. (2011) uses an accretion disc particle to represent both the black hole and its accretion disc. We have extrapolated and adapted this approach to simulations of Milky Way-sized galaxy mergers containing black holes and explored the impact of the various parameters

Andrey Beresnyak

Recently Perez et al [arXiv:1209.2011] wrote on the spectral slope of MHD turbulence claiming that it is consistent with -3/2. This work contains a number of errors, factual inaccuracies and puzzling methods in the interpretation of numerics. We argue that the numerical evidence that the authors presented is actually against -3/2 slope and the assumption of

Javier E. Cuchí, Alfred Molina, Eduardo Ruiz

We compare the results obtained from analytical perturbation theory and the AKM numerical code for an axistationary spacetime built from matching a rotating perfect fluid interior with the equation of state $ε-3p=4B$ of the simple MIT bag model and an asymptotically flat exterior. We discuss the behaviour of the error in the metric components of the analytic

Daniel R. Weisz, Andrew E. Dolphin, Evan D. Skillman, Jon Holtzman

We present preliminary results from a new HST archival program aimed at tightly constraining the ancient (>4 Gyr ago) star formation histories (SFHs) of the field populations of the SMC and LMC. We demonstrate the quality of the archival data by constructing HST/WFPC2-based color-magnitude diagrams (CMDs; M_{F555W} ~ +8) for 7 spatially diverse fields in the

Bryan R. Gillis, Michael J. Hudson, Thomas Erben, Catherine Heymans

We use weak gravitational lensing to analyse the dark matter halos around satellite galaxies in galaxy groups in the CFHTLenS dataset. This dataset is derived from the CFHTLS-Wide survey, and encompasses 154 sq. deg of high-quality shape data. Using the photometric redshifts, we divide the sample of lens galaxies with stellar masses in the range 10^9 Msun to

Weixiong Zhang

In the real world, insufficient information, limited computation resources, and complex problem structures often force an autonomous agent to make a decision in time less than that required to solve the problem at hand completely. Flexible and approximate computations are two approaches to decision making under limited computation resources. Flexible computa

Nevin Lianwen Zhang, Stephen S. Lee

There is much interest in using partially observable Markov decision processes (POMDPs) as a formal model for planning in stochastic domains. This paper is concerned with finding optimal policies for POMDPs. We propose several improvements to incremental pruning, presently the most efficient exact algorithm for solving POMDPs.

Nevin Lianwen Zhang

This paper is about reducing influence diagram (ID) evaluation into Bayesian network (BN) inference problems. Such reduction is interesting because it enables one to readily use one&#39;s favorite BN inference algorithm to efficiently evaluate IDs. Two such reduction methods have been proposed previously (Cooper 1988, Shachter and Peot 1992). This paper prop

Milan Studeny

AThe paper gives a few arguments in favour of the use of chain graphs for description of probabilistic conditional independence structures. Every Bayesian network model can be equivalently introduced by means of a factorization formula with respect to a chain graph which is Markov equivalent to the Bayesian network. A graphical characterization of such graph

Yoram Singer

A constant rebalanced portfolio is an asset allocation algorithm which keeps the same distribution of wealth among a set of assets along a period of time. Recently, there has been work on on-line portfolio selection algorithms which are competitive with the best constant rebalanced portfolio determined in hindsight. By their nature, these algorithms employ t

Ross D. Shachter

One of the benefits of belief networks and influence diagrams is that so much knowledge is captured in the graphical structure. In particular, statements of conditional irrelevance (or independence) can be verified in time linear in the size of the graph. To resolve a particular inference query or decision problem, only some of the possible states and probab

Raffaella Settimi, Jim Q. Smith

In this paper we investigate the geometry of the likelihood of the unknown parameters in a simple class of Bayesian directed graphs with hidden variables. This enables us, before any numerical algorithms are employed, to obtain certain insights in the nature of the unidentifiability inherent in such models, the way posterior densities will be sensitive to pr

Paola Sebastiani, Marco Ramoni

This paper describes a decision theoretic formulation of learning the graphical structure of a Bayesian Belief Network from data. This framework subsumes the standard Bayesian approach of choosing the model with the largest posterior probability as the solution of a decision problem with a 0-1 loss function and allows the use of more general loss functions a

Irina Rish, Kalev Kask, Rina Dechter

It was recently shown that the problem of decoding messages transmitted through a noisy channel can be formulated as a belief updating task over a probabilistic network [McEliece]. Moreover, it was observed that iterative application of the (linear time) Pearl&#39;s belief propagation algorithm designed for polytrees outperformed state of the art decoding al

David L. Poole

There is evidence that the numbers in probabilistic inference don&#39;t really matter. This paper considers the idea that we can make a probabilistic model simpler by making fewer distinctions. Unfortunately, the level of a Bayesian network seems too coarse; it is unlikely that a parent will make little difference for all values of the other parents. In this

Mark Alan Peot, Ross D. Shachter

The process of diagnosis involves learning about the state of a system from various observations of symptoms or findings about the system. Sophisticated Bayesian (and other) algorithms have been developed to revise and maintain beliefs about the system as observations are made. Nonetheless, diagnostic models have tended to ignore some common sense reasoning