March 2006 arXiv papers — page 24

Alexander Roitershtein

We consider transient random walks on a strip in a random environment. The model was introduced by Bolthausen and Goldsheid [Comm. Math. Phys. 214 (2000) 429--447]. We derive a strong law of large numbers for the random walks in a general ergodic setup and obtain an annealed central limit theorem in the case of uniformly mixing environments. In addition, we

Yun Jin Choi, Young-Jai Park, Chil-Min Kim, Jaewan Kim

We propose a new quantum secret sharing scheme using a single non-entangled qubit. In the scheme, by transmitting a qubit to the next party sequentially, a sender can securely transmit a secret message to $N$ receivers who could only decode the message cooperatively after randomly shuffling the polarization of the qubit. We explain this quantum secret sharin

R. K. Zamanov, M. F. Bode, C. H. F. Melo, R. Bachev

We have measured the projected rotational velocities (v sin i) of the mass donors for 29 S-type symbiotic stars using high resolution spectroscopic observations and the cross-correlation function (CCF) method. The results of the CCF have been controlled with synthetic spectra. The typical rotational velocity of the K and M giants in S-type symbiotics appeare

Diego Julio Cirilo-Lombardo

In this work, the solution of the Einstein equations for a slowly rotating black hole with Born-Infeld charge is obtained. Geometrical properties and horizons of this solution are analyzed. The conditions when the ADM mass (as in the nonlinear static cases) and the ADM angular momentum of the system have been modified by the non linear electromagnetic field

A. Iovan, D. B. Haviland, V. Korenivski

Asymmetric double tunnel barriers with the center electrode being a metal cluster in the quantum regime are studied. The zero dimensionality of the clusters used and the associated quantized energy spectra are manifest in well-defined steps in the current voltage characteristic (IVC). Record high current rectification ratios of 10000 for tunneling through su

Tony Lelievre, Mathias Rousset, Gabriel Stoltz

The computation of free energy differences through an exponential weighting of out of equilibrium paths (known as the Jarzynski equality) is often used for transitions between states described by an external parameter $λ$ in the Hamiltonian. We present here an extension to transitions between states defined by different values of some reaction coordinate, us

Hoshang Heydari

We propose a entanglement generating set for a general multipartite state based on the of concurrence. In particular, we show that concurrence for general multipartite states can be constructed by different classes of local operators which are defined by complement of positive operator valued measure on quantum phases. The entanglement generating set consist

Aranya B Bhattacherjee

We derive and study the Bloch and Bogoliubov spectrum of a Bose-Einstein condensate (BEC) confined in a one-dimensional optical superlattice (created by interference between a primary optical lattice and a secondary optical lattice of small strength), using the Bogoliubov approximation and the hydrodynamic theory with mode coupling. We show that a BEC in an

Kai-Yu Yang, C. T. Shih, C. P. Chou, S. M. Huang

In a recent review by Anderson and coworkers\cite{Vanilla}, it was pointed out that an early resonating valence bond (RVB) theory is able to explain a number of unusual properties of high temperature superconducting (SC) Cu-oxides. Here we extend previous calculations \cite{anderson87,FC Zhang,Randeria} to study more systematically low energy physical proper

Dennis S. Keeler

Let $X$ be a projective scheme over a field. We show that the vanishing cohomology of any sequence of coherent sheaves is closely related to vanishing under pullbacks by the Frobenius morphism. We also compare various definitions of ample locally free sheaf and show that the vanishing given by the Frobenius morphism is, in a certain sense, the strongest poss

C. Slezak, M. Jarrell, Th. Maier, J. Deisz

A numerically implementable Multi-scale Many-Body approach to strongly correlated electron systems is introduced. An extension to quantum cluster methods, it approximates correlations on any given length-scale commensurate with the strength of the correlations on the respective scale. Short length-scales are treated explicitly, long ones are addressed at a m

Tamas Gal

Analytical formulae for functional differentiation under simultaneous K-conservation constraints, with K the integral of some function of the functional variable, are derived, making the proper account for the simultaneous conservation of normalization and statistical averages, e.g., possible in functional differentiation in nonvariationally built physical t

Kenneth R. Brown, Robert J. Clark, Jaroslaw Labaziewicz, Philip Richerme

We demonstrate a method for loading surface electrode ion traps by electron impact ionization. The method relies on the property of surface electrode geometries that the trap depth can be increased at the cost of more micromotion. By introducing a buffer gas, we can counteract the rf heating assocated with the micromotion and benefit from the larger trap dep

Ilya Fushman, Jelena Vuckovic

We discuss the feasibility of a quantum nondemolition measurement (QND) of photon number based on cross phase modulation due to the Kerr effect in Photonic Crystal Waveguides (PCWs). In particular, we derive the equations for two modes propagating in PCWs and their coupling by a third order nonlinearity. The reduced group velocity and small cross-sectional a

Adam Miranowicz, Wieslaw Leonski

Schemes for optical-state truncation of two cavity modes are analysed. The systems, referred to as the nonlinear quantum scissors devices, comprise two coupled nonlinear oscillators (Kerr nonlinear coupler) with one or two of them pumped by external classical fields. It is shown that the quantum evolution of the pumped couplers can be closed in a two-qubit H

D. Ivanov, S. Wallentowitz

It is shown how the quantumness of atom-atom correlations in a trapped bosonic gas can be made observable. Application of continuous feedback control of the center of mass of the atomic cloud is shown to generate oscillations of the spatial extension of the cloud, whose amplitude can be directly used as a characterization of atom-atom correlations. Feedback

I. T. Durham

This doctoral dissertation presents an in-depth analysis of the first six chapters of Eddington's Fundamental Theory, sometimes referred to as his 'statistical' theory, in the context of discoveries and advancements made since its original publication in 1946. In particular, the analysis is focused on being in the context of the foundations of qu

Jian Wang, Quan Zhang, Chao-jing Tang

Recently, Cao et al. proposed a new quantum secure direct communication scheme using W state. In their scheme, the error rate introduced by an eavesdropper who takes intercept-resend attack, is only 8.3%. Actually, their scheme is just a quantum key distribution scheme because the communication parties first create a shared key and then encrypt the secret me

D. B. Lyjatsky, E. I. Shakhnovich

Statistical analysis of protein-protein interactions shows anomalously high frequency of homodimers [Ispolatov, I., et al. (2005) Nucleic Acids Res 33, 3629-35]. Furthermore, recent findings [Wright, C.F., et al. (2005) Nature 438, 878-81] demonstrate that maintaining low sequence identity is a key evolutionary mechanism that inhibits protein aggregation. He

John Swain

At least two significant roles for large scale quantum coherence in living systems have been suggested: Herbert Fröhlich's coherent excitations of nonlinearly coupled ensembles of large polarizable molecules, with frequencies in the microwave region, and Fritz Popp's coherent visible photon emission arising from metabolically active cells. The large

C. L. Herzenberg

Although cosmic expansion at very small distances is usually dismissed as entirely inconsequential, these extraordinarily small effects may in fact have a real and significant influence on our world. A calculation suggests that the minute recessional velocities associated with regions encompassed by extended bodies may have a role in creating the distinction

Markus Kress, Torsten Loeffler, Mark D. Thomson, Reinhard Doerner

The availability of few-cycle optical pulses opens a window to physical phenomena occurring on the attosecond time scale. In order to take full advantage of such pulses, it is crucial to measure and stabilise their carrier-envelope (CE) phase, i.e., the phase difference between the carrier wave and the envelope function. We introduce a novel approach to dete

R. van der Heijden, C. F. Carlstrom, J. A. P. Snijders, R. W. van der Heijden

Polymer filling of the air holes of Indium Phosphide based two-dimensional photonic crystals is reported. After infiltration of the holes with a liquid monomer and solidification of the infill in situ by thermal polymerization, complete filling is proven using scanning electron microscopy. Optical transmission measurements of a filled photonic crystal struct

Andrei P. Kirilyuk

Operation of autonomic communication networks with complicated user-oriented functions should be described as unreduced many-body interaction process. The latter gives rise to complex-dynamic behaviour including fractally structured hierarchy of chaotically changing realisations. We recall the main results of the universal science of complexity (physics/9806

J. D. Gillaspy, B. Blagojevic, A. Dalgarno, K. Fahey

After a brief introduction to the NIST EBIT facility, we present the results of three different types of experiments that have been carried out there recently: EUV and visible spectroscopy in support of the microelectronics industry, laboratory astrophysics using an x-ray microcalorimeter, and charge exchange studies using extracted beams of highly charged i

F. Ghasemi, Muhammad Sahimi, J. Peinke, M. Reza Rahimi Tabar

We describe a method for analyzing the stochasticity in the non-stationary data for the beat-to-beat fluctuations in the heart rates of healthy subjects, as well as those with congestive heart failure. The method analyzes the returns time series of the data as a Markov process, and computes the Markov time scale, i.e., the time scale over which the data are

Andrei P. Kirilyuk

Dynamics of arbitrary communication system is analysed as unreduced interaction process. The applied generalised, universally nonperturbative method of effective potential reveals the phenomenon of dynamic multivaluedness of competing system configurations forced to permanently replace each other in a causally random order, which leads to universally defined

S. G. Mashnik, K. K. Gudima, M. I. Baznat

This paper presents part of an internal LANL Progress Report on completion of the "S" and "G" versions of the improved Cascade-Exciton Model (CEM03.01) and the Los Alamos Quark-Gluon String Model (LAQGSM.03.01) codes. The "S" versions consider fragmentation of compound nuclei produced after the preequilibrium stage of reactions for ex

C. Ducoin, P. Chomaz, F. Gulminelli

We study the thermodynamics of asymmetric nuclear matter using a mean field approximation with a Skyrme effective interaction, in order to establish its phase diagram and more particularly the influence of isospin on the order of the transition. A new statistical method is introduced to study the thermodynamics of a multifluid system, keeping only one densit

PHENIX Collaboration, S. S. Adler

We report on two-particle azimuthal angle correlations between charged hadrons at forward/backward (deuteron/gold going direction) rapidity and charged hadrons at mid-rapidity in deuteron-gold (d+Au) and proton-proton (p+p) collisions at sqrt(s_NN) = 200 GeV. Jet structures are observed in the correlations which we quantify in terms of the conditional yield

Takeshi Ogasawara, Sadayoshi Toh

The relative dispersion process in two-dimensional free convection turbulence is investigated by direct numerical simulation. In the inertial range, the growth of relative separation, $r$, is expected as $<r^2(t)>\propto t^5$ according to the Bolgiano-Obukhov scaling. The result supporting the scaling is obtained with exit-time statistics. Detailed investiga

Avner Priel

The properties of the mean first passage time in a system characterized by multiple periodic attractors are studied. Using a transformation from a high dimensional space to 1D, the problem is reduced to a stochastic process along the path from the fixed point attractor to a saddle point located between two neighboring attractors. It is found that the time to

Martin Engman, Ricardo Cordero Soto

We uniquely and explicitly reconstruct the instantaneous intrinsic metric of the Kerr-Newman Event Horizon from the spectrum of its Laplacian. In the process we find that the angular momentum parameter, radius, area; and in the uncharged case, mass, can be written in terms of these eigenvalues. In the uncharged case this immediately leads to the unique and e

Hajime Moriya

This paper has been withdrawn.

Tamas Keleti, Mihail N. Kolountzakis

Let $G$ be a finite abelian group and $E$ a subset of it. Suppose that we know for all subsets $T$ of $G$ of size up to $k$ for how many $x \in G$ the translate $x+T$ is contained in $E$. This information is collectively called the $k$-deck of $E$. One can naturally extend the domain of definition of the $k$-deck to include functions on $G$. Given the group

Julia Pevtsova, Sarah Witherspoon

We define a rank variety for a module of a noncocommutative Hopf algebra $A = Λ\rtimes G$ where $Λ= k[X_1, ..., X_m]/(X_1^{\ell}, ..., X_m^{\ell})$, $G = ({\mathbb Z}/\ell{\mathbb Z})^m$, and $\text{char} k$ does not divide $\ell$, in terms of certain subalgebras of $A$ playing the role of &#34;cyclic shifted subgroups&#34;. We show that the rank variety of

Valentyna A. Groza, Ivan I. Kachuryk

The dual discrete $q$-ultraspherical polynomials $D_n^{(s)}(μ(x;s)|q)$ correspond to indeterminate moment problem and, therefore, have one-parameter family of extremal orthogonality relations. It is shown that special cases of dual discrete $q$-ultraspherical polynomials $D_n^{(s)}(μ(x;s)|q)$, when $s=q^{-1}$ and $s=q$, are directly connected with $q^{-1}$-H

F. Klebaner, R. Liptser

The Large Deviation Principle is established for stochastic models defined by past-dependent non linear recursions with small noise. In the Markov case we use the result to obtain an explicit expression for the asymptotics of exit time.

Norman Do, Paul Norbury

The moduli spaces of hyperbolic surfaces of genus g with n geodesic boundary components are naturally symplectic manifolds. Mirzakhani proved that their volumes are polynomials in the lengths of the boundaries by computing the volumes recursively. In this paper we give new recursion relations between the volume polynomials.

Tomislav Došlić, Darko Veljan

Using calculus we show how to prove some combinatorial inequalities of the type log-concavity or log-convexity. It is shown by this method that binomial coefficients and Stirling numbers of the first and second kinds are log-concave, and that Motzkin numbers and secondary structure numbers of rank 1 are log-convex. In fact, we prove via calculus a much stron

Tomislav Došlić

We consider log-convex sequences that satisfy an additional constraint imposed on their rate of growth. We call such sequences log-balanced. It is shown that all such sequences satisfy a pair of double inequalities. Sufficient conditions for log-balancedness are given for the case when the sequence satisfies a two- (or more-) term linear recurrence. It is sh

Peter Eichelsbacher, Tomasz Schreiber

Functionals of spatial point process often satisfy a weak spatial dependence condition known as stabilization. In this paper we prove process level moderate deviation principles (MDP) for such functionals, which are a level-3 result for empirical point fields as well as a level-2 result for empirical point measures. The level-3 rate function coincides with t

Philip Boalch

We will relate the surprising Regge symmetry of the Racah-Wigner 6j symbols to the surprising Okamoto symmetry of the Painleve VI differential equation. This then presents the opportunity to give a conceptual derivation of the Regge symmetry, as the representation theoretic analogue of the author&#39;s previous derivation of the Okamoto symmetry. [The result

Valerij G. Bardakov

For every group genetic code with finite number of generating and at most with one defining relation we introduce the braid group of this genetic code. This construction includes the braid group of Euclidean plane, the braid groups of closed orientable surfaces, B type groups of Artin-Brieskorn, and allow us to study all these groups with common point of vie

V. Heiermann, G. Muic

Let G be a quasi-split p-adic group. Under the assumption that the local coefficients $C_ψ$ defined with respect to $ψ$-generic tempered representations of standard Levi subgroups of G are regular in the negative Weyl chamber, we show that the standard module conjecture is true, which means that the Langlands quotient of a standard module is generic if and o

Horst Martini, Konrad J Swanepoel

We give a complete proof that in any finite-dimensional normed linear space a finite set of points has a minimal spanning tree in which the maximum degree is bounded above by the strict Hadwiger number of the unit ball, i.e., the largest number of unit vectors such that the distance between any two is larger than 1.

Bernard Brighi- Senoussi Guesmia

This paper is concerned with the convergence of the solution of general elliptic boundary value problems in cylindrical domain, when some directions of the domain go to infinity.

Z. Arvasi, E. Ulualan

This article investigates the homotopy theory of simplicial commutative algebras with a view to homological applications.

Francis Comets

In this paper, we consider directed polymers in random environment with long range jumps in discrete space and time. We extend to this case some techniques, results and classifications known in the usual short range case. However, some properties are drastically different when the underlying random walk belongs to the domain of attraction of an $\a$-stable l

Daniel Krashen

Grothendieck-Chow motives of quadric hypersurfaces have provided many insights into the theory of quadratic forms. Subsequently, the landscape of motives of more general projective homogeneous varieties has begun to emerge. In particular, there have been many results which relate the motive of a one homogeneous variety to motives of other simpler or smaller

Eric S. Brussel

We study a continuous family of norm-preserving isometries of the p-adic unit disk, given as interpolations of a common arithmetic function, the q-analog of the identity, for principal p-adic units q. We show that the fixed point set is trivial except when p=3 and q is a generator of the principal 3-adic units; in that case the isometry given by each q has a

Victor Batyrev

Let $Δ\subset \R^n$ be an $n$-dimensional lattice polytope. It is well-known that $h_Δ^*(t) := (1-t)^{n+1} \sum_{k \geq 0} |kΔ\cap \Z^n| t^k $ is a polynomial of degree $d \leq n$ with nonnegative integral coefficients. Let $AGL(n, \Z)$ be the group of invertible affine integral transformations which naturally acts on $\R^n$. For a given polynomial $h^* \in

J. -R. Chazottes, P. Collet, C. Kuelske, F. Redig

We present a new and simple approach to concentration inequalities for functions around their expectation with respect to non-product measures, i.e., for dependent random variables. Our method is based on coupling ideas and does not use information inequalities. When one has a uniform control on the coupling, this leads to exponential concentration inequalit

Benoit Charbonneau

The main result is a computation of the Nahm transform of a SU(2)-instanton over RxT^3, called spatially-periodic instanton. It is a singular monopole over T^3, a solution to the Bogomolny equation, whose rank is computed and behavior at the singular points is described.

Graham Everest, Gerard Mclaren, Tom Ward

Silverman proved the analogue of Zsigmondy&#39;s Theorem for elliptic divisibility sequences. For elliptic curves in global minimal form, it seems likely this result is true in a uniform manner. We present such a result for certain infinite families of curves and points. Our methods allow the first explicit examples of the elliptic Zsigmondy Theorem to be ex

Zheng Ze Ma

We study the Moyal commutators and their expectation values between vacuum states and non-vacuum states for noncommutative scalar field theory. For noncommutative $ϕ^{\star4}$ scalar field theory, we derive its energy-momentum tensor from translation transformation and Lagrange field equation. We generalize the Heisenberg and quantum motion equations to the

S. R. Slabospitsky

This contribution provides brief descriptions the current status of the basic Monte Carlo event generators for top-quark production and decays.

Tim Ledwig, Hyun-Chul Kim, Antonio Silva, Klaus Goeke

We investigate the electric form factors and charge radii of the pentaquark baryons within the framework of the chiral quark-soliton model. We consider the rotational $1/N_c$ and linear $m_s$ corrections, assuming isospin symmetry and employing the symmetry-conserving quantization. The flavor-decomposed charge densities of the $Θ^+$ are presented. The electr

Giampiero Passarino, Sandro Uccirati

A comprehensive study is performed of two-loop Feynman diagrams with three external legs which, due to the exchange of massless gauge-bosons, give raise to infrared and collinear divergencies. Their relevance in assembling realistic computations of next-to-next-to-leading corrections to physical observables is emphasised. A classification of infrared singula

Hong-Wei Ke, Yan-Ming Yu, Yi-Bing Ding, Xin-Heng Guo

The resonance $D_{sJ}(2632)$ observed by SELEX, has attracted great interests and meanwhile brought up serious dispute. Its spin-parity, so far has not finally determined and if it exists, its quark-structure might be exotic. Following the previous literature where $D_{sJ}(2632)$ is assumed to be a radial-excited state of $1^-$, we consider the possibilities

Anadi Canepa

Supersymmetry, if realized in Nature, predicts the existence of new particles, as chargino and neutralino, which might manifest themselves with peculiar signatures. Three leptons and large missing transverse energy in the event could signal their associated production. We report the latest results of the search performed by the CDF Collaboration in proton-an

D. J. Cirilo-Lombardo

In this work a new asymptotically flat solution of the coupled Einstein-Born-Infeld equations for a static spherically symmetric space-time is obtained. When the intrinsic mass is zero the resulting spacetime is regular everywhere, in the sense given by B. Hoffmann and L. Infeld in 1937, and the Einstein-Born-Infeld theory leads to the identification of the

Priya Sivakumar

We present simple implementations of Kak&#39;s three-stage quantum cryptography protocol. The case where the transformation is applied to more than one qubit at the same time is also considered.

Nihar Jindal

A multiple antenna broadcast channel with perfect channel state information at the receivers is considered. If each receiver quantizes its channel knowledge to a finite number of bits which are fed back to the transmitter, the large capacity benefits of the downlink channel can be realized. However, the required number of feedback bits per mobile must be sca

Nihar Jindal

Multiple transmit antennas in a downlink channel can provide tremendous capacity (i.e. multiplexing) gains, even when receivers have only single antennas. However, receiver and transmitter channel state information is generally required. In this paper, a system where each receiver has perfect channel knowledge, but the transmitter only receives quantized inf

Chau Yuen, Yong Liang Guan, Tjeng Thiang Tjhung

In this paper, we consider a quasi-orthogonal (QO) space-time block code (STBC) with minimum decoding complexity (MDC-QO-STBC). We formulate its algebraic structure and propose a systematic method for its construction. We show that a maximum-likelihood (ML) decoder for this MDC-QOSTBC, for any number of transmit antennas, only requires the joint detection of

Tobias Riege, Jörg Rothe, Holger Spakowski, Masaki Yamamoto

The 3-domatic number problem asks whether a given graph can be partitioned intothree dominating sets. We prove that this problem can be solved by a deterministic algorithm in time 2.695^n (up to polynomial factors). This result improves the previous bound of 2.8805^n, which is due to Fomin, Grandoni, Pyatkin, and Stepanov. To prove our result, we combine an

Yuan Feng, Runyao Duan, Zhengfeng Ji, Mingsheng Ying

We apply the notion of quantum predicate proposed by D&#39;Hondt and Panangaden to analyze a purely quantum language fragment which describes the quantum part of a future quantum computer in Knill&#39;s architecture. The denotational semantics, weakest precondition semantics, and weakest liberal precondition semantics of this language fragment are introduced

Sohrab Ismail-Beigi

First principles methods based on periodic boundary conditions are used extensively by materials theorists. However, applying these methods to systems with confined electronic states entails the use of large unit cells in order to avoid artificial image interactions. We present a general approach for truncating the Coulomb interaction that removes image effe

M. H. Szymanska, J. Keeling, P. B. Littlewood

We study spontaneous quantum coherence in an out of equilibrium system, coupled to multiple baths describing pumping and decay. For a range of parameters describing coupling to, and occupation of the baths, a stable steady-state condensed solution exists. The presence of pumping and decay significantly modifies the spectra of phase fluctuations, leading to c

X. Y. Jin, J. Lisenfeld, Y. Koval, A. Lukashenko

We have investigated macroscopic quantum tunneling in Bi$_2$Sr$_2$CaCu$_2$O$_{8+δ}$ intrinsic Josephson junctions at millikelvin temperatures using microwave irradiation. Measurements show that the escape rate for uniformly switching stacks of N junctions is about $N^2$ times higher than that of a single junction having the same plasma frequency. We argue th

Andrea Gauzzi, S. Takashima, N. Takeshita, C. Terakura

We measured the electrical resistivity, $\varrho(T)$, of superconducting CaC$\_6$ at ambient and high pressure up to 16 GPa. For $P \leq$8 GPa, we found a large increase of $T\_c$ with pressure from 11.5 up to 15.1 K. At 8 GPa, $T\_c$ drops and levels off at 5 K above 10 GPa. Correspondingly, the residual $\varrho$ increases by $\approx$ 200 times and the $\

Eran Sela, Yuval Oreg, Felix von Oppen, Jens Koch

Low temperature transport through a quantum dot in the Kondo regime proceeds by a universal combination of elastic and inelastic processes, as dictated by the low-energy Fermi-liquid fixed point. We show that as a result of inelastic processes, the charge detected by a shot-noise experiment is enhanced relative to the noninteracting situation to a universal

N. Garcia, Ming Bai, Yonghua Lu, M. Munoz

Theory and a vast set of experimental work in metals, since a century, appear to show that the mean free path of conduction electrons in a real metal is about the min (bulk mean free path, smallest transversal size of the metal), a result that was already proposed by J. J. Thomson in 1901. This establishes, as discussed in this work, serious difficulties to

Manuel I. Marques, Julio A. Gonzalo

The behavior of the local mode potential energy in the unit cell of BaTiO3 is studied by effective Hamiltonian numerical simulations. The study is focused on the evolution of the potential minimum felt by the Ti ion. At the paraelectric phase, the single instantaneous minimum is located at one of eight off-centered regions at the body diagonals of the unit c

E. G. Semerdzhieva, T. L. Boyadjiev, Yu. M. Shukrinov

The transition from the model of a long Josephson junction of variable width to the model of a junction with a coordinate-dependent Josephson current amplitude is effected through a coordinate transformation. This establishes the correspondence between the classes of Josephson junctions of variable width and quasi-one-dimensional junctions with a variable th

G. Giovannelli, S. Natali, B. Bozzini, D. Manno

In this research, we report on the compositional, microstructural and crystallographic properties of a lead coin which has been regarded for many years as a genuine silver coin minted in the Southern Italy in the course of the 4th century BC. The material characterisation of this object allowed detecting an ancient forging technology, not previously reported

F. Campelo, A. Hernandez-Machado

A phase-field model that takes into account the bending energy of fluid vesicles is presented. The Canham-Helfrich model is derived in the sharp-interface limit. A dynamic equation for the phase-field has been solved numerically to find stationary shapes of vesicles with different topologies and the dynamic evolution towards them. The results are in agreemen

Tarcisio Marciano Rocha Filho, Annibal Figueiredo, Marco Antonio Amato

We offer o reply for the comments of Rapisarda et al. cond-mat/0601409 on our letter &#34;Entropy of Classical Systems with Long Range Interactios&#34;, published in Phys. Rev. Lett. Vol 95 (2005) 190601.

F. Bert, P. Mendels, A. Olariu, N. Blanchard

MuSR experiments have been performed on powder sample of the &#34;ordered spin ice&#34; Tb$_2$Sn$_2$O$_7$ pyrochlore compound. At base temperature (T=35mK) the muon relaxation is found to be of dynamical nature which demonstrates that strong fluctuations persist below the ferromagnetic transition (T_C=0.87K). Hints of long range order appear as oscillations

A. S. Mishchenko, N. Nagaosa

We present a numerical study of the isotope effect on the angle resolved photoemission spectra (ARPES) in the undoped cuprates. By the systematic-error-free Diagrammatic Monte Carlo method, the Lehman spectral function of a single hole in the tt&#39;t&#39;&#39;-J model in the regime of intermediate and strong couplings to optical phonons is calculated for no

K. Hamaya, S. Masubuchi, K. Hirakawa, S. Ishida

We study the edge-channel transport of electrons in a high-mobility Si/SiGe two-dimensional electron system in the quantum Hall regime. By selectively populating the spin-resolved edge channels, we observe suppression of the scattering between two edge channels with spin-up and spin-down. In contrast, when the Zeeman splitting of the spin-resolved levels is

Hideo Yoshioka, Masahisa Tsuchiizu, Hitoshi Seo

Finite-temperature charge-ordering phase transition in quasi one-dimensional (1D) molecular conductors is investigated theoretically, based on a quasi 1D extended Hubbard model at quarter filling with interchain Coulomb repulsion $V_\perp$. The interchain term is treated within mean-field approximation whereas the 1D fluctuations in the chains are fully take

Ryo Shibata, Yukio Saito, Hiroyuki Hyuga

Diffusion effect on chirality selection in a two-dimensional reaction-diffusion model is studied by the Monte Carlo simulation. The model consists of achiral reactants A which turn into either of the chiral products, R or S, in a solvent of chemically inactive vacancies V. The reaction contains the nonlinear autocatalysis as well as recycling process, and th

Ivailo Dimov, Chetan Nayak

We consider various incommensurate (IC) order parameters for electrons on a square lattice which reduce to $d_{x^2-y^2}$-density wave (DDW) order when the ordering wavevector ${\bf Q}\to (π,π)$. We describe the associated charge and current distributions and their experimental signatures. Such orders can arise at the mean-field level in extended Hubbard mode

Radhakrishnan Nagarajan

Surrogate testing is used widely to determine the nature of the process generating the given empirical sample. In the present study, the usefulness of phase-randomized surrogates, amplitude adjusted Fourier transform (AAFT) and iterated amplitude adjusted Fourier transform (IAAFT) surrogates on statistical inference of linearly correlated noise with non-Gaus

H. I. Jørgensen, K. Grove-Rasmussen, T. Novotný, K. Flensberg

We fabricated reproducible high transparency superconducting contacts consisting of superconducting Ti/Al/Ti trilayers to gated single-walled carbon nanotubes (SWCNTs). The reported semiconducting SWCNT have normal state differential conductance up to $3e^2/h$ and exhibit clear Fabry-Perot interference patterns in the bias spectroscopy plot. We observed subh

P. Bertet, C. J. P. M. Harmans, J. E. Mooij

We propose a scheme to couple two superconducting charge or flux qubits biased at their symmetry points with unequal energy splittings. Modulating the coupling constant between two qubits at the sum or difference of their two frequencies allows to bring them into resonance in the rotating frame. Switching on and off the modulation amounts to switching on and

Catherine L. Buchanan, Joel H. Kastner, William J. Forrest, Bruce J. Hrivnak

We have produced an atlas of Spitzer Infrared Spectrograph (IRS) spectra of mass-losing, evolved stars in the Large Magellanic Cloud. These stars were selected to have high mass-loss rates and so contribute significantly to the return of processed materials to the ISM. Our high-quality spectra enable the determination of the chemistry of the circumstellar en

Catherine L. Buchanan, Jack F. Gallimore, Christopher P. O&#39;Dea, Stefi A. Baum

We present the results of IRS low-resolution spectroscopy of 51 Seyfert galaxies, part of a large Spitzer observing program to determine the mid-to-far infrared spectral energy distributions of a well-defined sample of 87 nearby, 12 micron-selected Seyferts. We find that the spectra clearly divide into groups based on their continuum shapes and spectral feat

Sudip Bhattacharyya, Tod E. Strohmayer

Non-photospheric-radius-expansion (non-PRE) double-peaked bursts may be explained in terms of spreading (and temporary stalling) of thermonuclear flames on the neutron star surface, as we argued in a previous study of a burst assuming polar ignition. Here we analyze Rossi X-ray Timing Explorer (RXTE) Proportional Counter Array (PCA) data of such a burst (but

J. Martin Laming, Una Hwang, Balint Radics, Gergely Lekli

Probably not, but it is interesting nevertheless to investigate just how close Cas A might have come to generating such an event. Focusing on the northeast jet filaments, we analyze the polar regions of the recently acquired very deep 1 Ms Chandra X-ray observation. We infer that the so-called &#34;jet&#34; regions are indeed due to jets emanating from the e

Ken&#39;ichi Nomoto, Nozomu Tominaga, Hideyuki Umeda, Chiaki Kobayashi

The abundance patterns of extremely metal-poor (EMP) stars provide us with important information on nucleosynthesis in supernovae (SNe) formed in a Pop III or EMP environment, and thus on the nature of the first stars in the Universe. We review nucleosynthesis yields of various types of those SNe, focusing on core-collapse (black-hole-forming) SNe with vario

Ken&#39;ichi Nomoto, Tomoharu Suzuki, Jinsong Deng, Tatsuhiro Uenishi

Among the important issues in identifying the progenitor system of Type Ia supernovae (SNe Ia), we focus mostly on circumstellar interaction in SN 2002ic, and give brief discussion on the controversial issues of the effects of rotation in merging double degenerates and steady hydrogen shell burning in accreting white dwarfs. SN 2002ic is a unique supernova w

V. Suleimanov, A. Ibragimov

The parameters of ten supersoft X-ray sources (RX J0439.8-6809, RX J0513.9-6951, RX J0527.8-6954, CAL 87, CAL 83, 1E 0035.4-7230, RX J0048.4-7332, 1E 0056.8-7154, RX J0019.8 +2156, RX J0925.7-4758) observed by ROSAT obtained using blanketing LTE model atmospheres are analyzed. The consistency of the resulting parameters with a model with stable/recurrent bur

A. Ibragimov, V. Suleimanov, A. Vikhlinin, N. Sakhibullin

ROSAT spectra of 11 supersoft X-ray sources (RX J0439.8-6809, RX J0513.9-6951, RX J0527.8-6954, CAL 87, CAL 83, 1E 0035.4-7230, RX J0048.4-7332, 1E 0056.8-7154, RX J0019.8 +2156, RX J0925.7-4758, AG Draconis) are approximated with theoretical spectra obtained in LTE models for the atmospheres of hot white dwarfs with line blanketing. The confidence intervals

James M. De Buizer

The young massive stellar object G35.20-0.74 was observed in the mid-infrared using T-ReCS on Gemini South. Previous observations have shown that the near infrared emission has a fan-like morphology that is consistent with emission from the northern lobe of a bipolar radio jet known to be associated with this source. Mid-infrared observations presented in th

E. A. Bergin, S. Maret, F. F. S. van der Tak, J. Alves

We present a direct comparison of a chemical/physical model to multitransitional observations of C18O and 13CO towards the Barnard 68 pre-stellar core. These observations provide a sensitive test for models of low UV field photodissociation regions and offer the best constraint on the gas temperature of a pre-stellar core. We find that the gas temperature of

N. J. Rodriguez-Fernandez, J. Braine, N. Brouillet, F. Combes

The CII 158 microns line is the most important coolant of the interstellar medium in galaxies but substantial variations are seen from object to object. The main source of the emission at a galactic scale is still poorly understood. Previous studies of the CII emission in galaxies have a resolution of several kpc or more so the observed emission is an averag

Albert Zijlstra, K. Gesicki, J. R. Walsh, D. Pequignot

The identification of two new Planetary Nebulae in the Sagittarius Dwarf Spheroidal Galaxy (Sgr) is presented. This brings the total number to four. The first, StWr 2-21, belongs to the main body of Sgr. The second, the halo PN BoBn 1, has a location, distance and velocity in agreement with the leading tidal tail of Sgr. We estimate that 10 per cent of the G