October 2007 arXiv papers — page 9
Showing 801–900 of 5,810 papers
Wytler Cordeiro dos Santos
The Laser Interferometer Space Antenna (LISA) mission will use advanced technologies to achieve its science goals: the direct detection of gravitational waves, the observation of signals from compact (small and dense) stars as they spiral into black holes, the study of the role of massive black holes in galaxy evolution, the search for gravitational wave emi
M. Yu. Petrov, I. V. Ignatiev, S. V. Poltavtsev, A. Greilich
The hyperfine interaction of an electron with nuclei in the annealed self-assembled InAs/GaAs quantum dots is theoretically analyzed. For this purpose, the annealing process, and energy structure of the quantum dots are numerically modeled. The modeling is verified by comparison of the calculated optical transitions and of the experimental data on photolumin
Melissa Jerkins, Matthias Schröter, Harry L. Swinney, Tim J. Senden
Using sedimentation to obtain precisely controlled packings of noncohesive spheres, we find that the volume fraction $ϕ_{\rm RLP}$ of the loosest mechanically stable packing is in an operational sense well defined by a limit process. This random loose packing volume fraction decreases with decreasing pressure $p$ and increasing interparticle friction coeffic
Xiuxiong Chen, Weiyong He
We consider the formation of singularities along the Calabi flow with the assumption of the uniform Sobolev constant. In particular, on Kähler surface we show that any "maximal bubble" has to be a scalar flat ALE Kähler metric. In some certain classes on toric Fano surface, the Sobolev constant is a priori bounded along the Calabi flow with small Cal
Aaron Bergman, Daniel Robbins
We consider compactifications of type II string theory in which a d-dimensional torus is fibered over a base X. In string theory, the transition functions of this fibration need not be simply diffeomorphisms of T^d but can involve elements of the T-duality group Spin(d,d,Z). We precisely define the notion of a T-fold with NSNS flux. Given such a T-fold, we d
AM Semikhatov
The procedure in [Fuchs et al.] to obtain a fusion algebra from the modular transformation of characters in logarithmic conformal field models is extended to the (p,p') logarithmic models. The resulting fusion algebra coincides with the Grothendieck ring of the quantum group of the (p,p') model.
Xu Du, Ivan Skachko, Eva Y. Andrei
The Josephson Effect and Superconducting Proximity Effect were observed in Superconductor -Graphene-Superconductor (SGS) Josephson junctions with coherence lengths comparable to the distance between the superconducting leads. By comparing the measured temperature and doping dependence of the supercurrent and the proximity induced sub-gap features (multiple A
Rafael A. Porto
We generalize the effective point particle approach to black hole dynamics to include spin. In this approach dissipative effects are captured by degrees of freedom localized on the wordline. The absorptive properties of the black hole are determined by correlation functions which can be matched with the graviton absorption cross section in the long wavelengt
Lutz Mattner
For one-sample level $α$ tests $ψ_m$ based on independent observations $X_1,...,X_m$, we prove an asymptotic formula for the actual level of the test rejecting if at least one of the tests $ψ_{n},...,ψ_{n+k}$ would reject. For $k=1$ and usual tests at usual levels $α$, the result is approximately summarized by the title of this paper. Our method of proof, re
Karsten Jedamzik
The Big Bang nucleosynthesis (BBN) in the presence of charged massive particles (CHAMPs) is studied in detail. All currently known effects due to the existence of bound states between CHAMPs and nuclei, including possible late-time destruction of Li6 and Li7 are included. The study sets conservative bounds on CHAMP abundances in the decay time range 3x10^2 s
Classification of Finite Dimensional Modular Lie Superalgebras with Indecomposable Cartan Matrix
math.RTSofiane Bouarroudj, Pavel Grozman, Dimitry Leites
Finite dimensional modular Lie superalgebras over algebraically closed fields with indecomposable Cartan matrices are classified under some technical, most probably inessential, hypotheses. If the Cartan matrix is invertible, the corresponding Lie superalgebra is simple otherwise the quotient of the derived Lie superalgebra modulo center is simple (if its ra
Reply to the Comment on "Passage Times for Unbiased Polymer Translocation through a Narrow Pore"
cond-mat.softDebabrata Panja, Gerard T. Barkema
Theoretical derivation and numerical confirmation are provided for the scaling of pore-blockade times as $N^{2+\nu}$ for unbiased translocation in two and three dimensions, with $N$ as the polymer length and $\nu$ as the Flory exponent of the polymer. The polymer performs Rouse dynamics.
D. Porras, F. Marquardt, J. von Delft, J. I. Cirac
Trapped ions arranged in Coulomb crystals provide us with the elements to study the physics of a single spin coupled to a boson bath. In this work we show that optical forces allow us to realize a variety of spin-boson models, depending on the crystal geometry and the laser configuration. We study in detail the Ohmic case, which can be implemented by illumin
Robert S. Whitney, Philippe Jacquod, Cyril Petitjean
We investigate the effect of dephasing/decoherence on quantum transport through open chaotic ballistic conductors in the semiclassical limit of small Fermi wavelength to system size ratio, $λ_F/L << 1$. We use the trajectory-based semiclassical theory to study a two-terminal chaotic dot with decoherence originating from: (i) an external closed quantum chaoti
P. A. Boyle, A. Jüttner, R. D. Kenway, C. T. Sachrajda
We present the first results for the Kl3 form factor from simulations with 2+1 flavours of dynamical domain wall quarks. Combining our result, namely f_+(0)=0.964(5), with the latest experimental results for Kl3 decays leads to |V_{us}|=0.2249(14), reducing the uncertaintity in this important parameter. For the O(p^6) term in the chiral expansion we obtain Δ
Michael Martin Nieto
Analysis of the radio tracking data from the Pioneer 10/11 spacecraft at distances between about 20 - 70 AU from the Sun has indicated the presence of an unmodeled, small, constant, Doppler blue shift which can be interpreted as a constant acceleration of a_P= (8.74 \pm 1.33) \times 10^{-8} cm/s^2 directed approximately towards the Sun. In addition, there is
Shao-Long Chen, Xiao-Gang He, Xue-Peng Hu, Yi Liao
Unparticle $\U$ with scaling dimension $d_\U$ has peculiar thermal properties due to its unique phase space structure. We find that the equation of state parameter $ω_\U$, the ratio of pressure to energy density, is given by $1/(2d_\U +1)$ providing a new form of energy in our universe. In an expanding universe, the unparticle energy density $ρ_\U(T)$ evolve
Kurusch Ebrahimi-Fard, Frederic Patras
This paper introduces a new Lie-theoretic approach to the computation of counterterms in perturbative renormalization. Contrary to the usual approach, the devised version of the Bogoliubov recursion does not follow a linear induction on the number of loops. It is well-behaved with respect to the Connes-Kreimer approach: that is, the recursion takes place ins
F. Marty Ytreberg
We compute absolute binding affinities for two ligands bound to the FKBP protein using non-equilibrium unbinding simulations. The methodology is straight-forward, requiring little or no modification to many modern molecular simulation packages. The approach makes use of a physical pathway, eliminating the need for complicated alchemical decoupling schemes. R
G. Fabbiano, N. J. Brassington, A. Zezas, s. Zepf
Our campaign of deep monitoring observations with {\it Chandra} of the nearby elliptical galaxy NGC 3379 has lead to the detection of nine globular cluster (GC) and 53 field low mass X-ray binaries (LMXBs) in the joint {\it Hubble}/{\it Chandra} field of view of this galaxy. Comparing these populations, we find a highly significant lack of GC LMXBs at the lo
LHCb collaboration, Johan Blouw
The LHCb experiment will search for New Physics in Bs mixing. The Bs mixing phase will be extracted from the measurement of the time-dependent CP asymmetry in exclusive Bs decays governed by the b -> ccbar s quark-level transition. Large New Physics effects can be discovered or excluded with the data collected during the very first physics run of LHC. Based
Michael J. Tambe, Nicola Bonini, Nicola Marzari
The behavior of metals at high pressure is of great importance to the fields of shock physics, geophysics, astrophysics, and nuclear materials. In order to further understand the properties of metals at high pressures we studied the equation of state of aluminum using first-principles techniques up to 2500 GPa, pressures within reach of the planned L.L.N.L.
F. Cardone, G. Cherubini, R. Mignani, W. Perconti
We report the results obtained by cavitating water solutions of iron salts (iron chloride and iron nitrate) with different concentrations at different ultrasound powers. In all cases we detected a neutron radiation well higher than the background level. The neutron production is perfectly reproducible and can at some extent be controlled. These evidences for
Ruth A. Daly, Matthew P. Mory, C. P. O'Dea, P. Kharb
Physical sizes of extended radio galaxies can be employed as a cosmological "standard ruler", using a previously developed method. Eleven new radio galaxies are added to our previous sample of nineteen sources, forming a sample of thirty objects with redshifts between 0 and 1.8. This sample of radio galaxies are used to obtain the best fit cosmologic
S. Actis, M. Czakon, J. Gluza, T. Riemann
We derive the two-loop corrections to Bhabha scattering from heavy fermions using dispersion relations. The double-box contributions are expressed by three kernel functions. Convoluting the perturbative kernels with fermionic threshold functions or with hadronic data allows to determine numerical results for small electron mass m_e, combined with arbitrary v
Jean-Pierre Demailly, Nefton Pali
We prove the existence and uniqueness of the solutions of some very general type of degenerate complex Monge-Amp\`ere equations. This type of equations is precisely what is needed in order to construct K\"ahler-Einstein metrics over irreducible singular K\"ahler spaces with ample or trivial canonical sheaf and singular K\"ahler-Einstein metrics over varietie
Mikhail Belolipetsky
We show that degrees of the real fields of definition of arithmetic Kleinian reflection groups are bounded by 35.
Photoluminescence modification by high-order photonic band with abnormal dispersion in ZnO inverse opal
physics.opticsHeeso Noh, Michael Scharrer, Mark A. Anderson, Robert P. H. Chang
We measured the angle- and polarization-resolved reflection and photoluminescence spectra of ZnO inverse opals. Significant enhancement of spontaneous emission is observed. The enhanced emission not only has good directionality but also can be linearly polarized. A detailed theoretical analysis and numerical simulation reveal that such enhancement is caused
Andrew Baker, Birgit Richter
Let E_n be the n-th Lubin-Tate spectrum at a prime p. There is a commutative S-algebra E^{nr}_n whose coefficients are built from the coefficients of E_n and contain all roots of unity whose order is not divisible by p. For odd primes p we show that E^{nr}_n does not have any non-trivial connected finite Galois extensions and is thus separably closed in the
J. Fleischer, J. Gluza, K. Kajda, T. Riemann
We report on tensor reduction of five point integrals needed for the evaluation of loop-by-loop corrections to Bhabha scattering. As an example we demonstrate the calculation of the rank two tensor integral with cancellation of the spurious Gram determinant in the denominator. The reduction scheme is worked out for arbitrary five point processes.
Creation of resilient entangled states and a resource for measurement-based quantum computation with optical superlattices
cond-mat.otherB. Vaucher, A. Nunnenkamp, D. Jaksch
We investigate how to create entangled states of ultracold atoms trapped in optical lattices by dynamically manipulating the shape of the lattice potential. We consider an additional potential (the superlattice) that allows both the splitting of each site into a double well potential, and the control of the height of potential barrier between sites. We use s
Xiaohu Yang, H. J. Mo, Frank C. van den Bosch
We investigate various halo occupation statistics using a large galaxy group catalogue constructed from the SDSS DR4 with an adaptive halo-based group finder. The conditional luminosity function (CLF) is measured separately for all, red and blue galaxies, as well as in terms of central and satellite galaxies. The CLFs for central and satellite galaxies can b
Two-step Doppler cooling of a three-level ladder system with an intermediate metastable level
quant-phCaroline Champenois, Gaetan Hagel, Martina Knoop, Marie Houssin
Doppler laser cooling of a three-level ladder system using two near-resonant laser fields is analyzed in the case of the intermediate level being metastable while the upper level is short-lived. Analytical as well as numerical results for e.g. obtainable scattering rates and achievable temperatures are presented. When appropriate, comparisons with two-level
M. Mihailescu
High derivative terms do not play a major role in field theories because of the associated complexity and inherent difficulty in connecting these terms to physically measurable quantities. A role for higher derivative terms is analyzed for the case of field theories used to describe phase separated systems. In these theories, higher derivative terms are dire
Nan Li, Dominik J. Schwarz
Due to the non-commutation of spatial averaging and temporal evolution, inhomogeneities and anisotropies (cosmic structures) influence the evolution of the averaged Universe via the cosmological backreaction mechanism. We study the backreaction effect as a function of averaging scale in a perturbative approach up to higher orders. We calculate the hierarchy
M. Castellana, G. Montani
Quantization of systems with constraints can be carried on with several methods. In the Dirac formulation the classical generators of gauge transformations are required to annihilate physical quantum states to ensure their gauge invariance. Carrying on BRST symmetry it is possible to get a condition on physical states which, differently from the Dirac method
Samson Saneblidze
For an abelian category, a category equivalent to its derived category is constructed by means of specific projective (injective) multicomplexes, the so-called homological resolutions.
Entangling the optical frequency comb: simultaneous generation of multiple 2x2 and 2x3 continuous-variable cluster states in a single optical parametric oscillator
quant-phHussain Zaidi, Nicolas C. Menicucci, Steven T. Flammia, Russell Bloomer
We report on our research effort to generate large-scale multipartite optical-mode entanglement using as few physical resources as possible. We have previously shown that cluster- and GHZ-type N-partite continuous-variable entanglement can be obtained in an optical resonator that contains a suitably designed second-order nonlinear optical medium, pumped by a
G. Dvali, H. B. Nielsen, N. Tetradis
We study the dynamical localization of a massless gauge field on a lower-dimensional surface (2-brane). In flat space, the necessary and sufficient condition for this phenomenon is the existence of confinement in the bulk. The resulting configuration is equivalent to a dual Josephson junction. This duality leads to an interesting puzzle, as it implies that a
L. Derkacz, L. Jakobczyk
We consider a pair of three - level atoms interacting with a common vacuum and analyze the process of entanglement production due to spontaneous emission. We show that in the case of closely separated atoms, collective damping can generate robust entanglement of the asymptotic states.
Masahiko Yoshinaga
A free multiarrangement of rank $k$ is defined to be extendable if it is obtained from a simple rank $(k+1)$ free arrangement by the natural restriction to a hyperplane (in the sense of Ziegler). Not all free multiarrangements are extendable. We will discuss extendability of free multiarrangements for a special class. We also give two applications. The first
Roberto Pereira
We generalize a model recently proposed for Euclidean quantum gravity to the case of Lorentzian signature. The main features of the Euclidean model are preserved in the Lorentzian one. In particular, the boundary Hilbert space matches the one of SU(2) loop quantum gravity. As in the Euclidean case, the model can be obtained from the Lorentzian Barrett-Crane
Julien Roth
In this article, we prove new stability results for almost-Einstein hypersurfaces of the Euclidean space, based on previous eigenvalue pinching results. Then, we deduce some comparable results for almost umbilical hypersurfaces.
Kazuo Fujikawa
We present an elementary and explicit proof of the separability criterion for continuous variable two-party Gaussian systems. Our proof is based on an elementary formulation of uncertainty relations and an explicit determination of squeezing parameters for which the P-representation condition saturates the $Sp(2,R)\otimes Sp(2,R)$ invariant separability cond
Elena Magliaro, Claudio Perini, Carlo Rovelli
We introduce a technique for testing the semiclassical limit of a quantum gravity vertex amplitude. The technique is based on the propagation of a semiclassical wave packet. We apply this technique to the newly introduced "flipped" vertex in loop quantum gravity, in order to test the intertwiner dependence of the vertex. Under some drastic simplifica
Juliane Behrend, Iain A. Brown, Georg Robbers
We reformulate the averaged Einstein equations in a form suitable for use with Newtonian gauge linear perturbation theory and track the size of the modifications to standard Robertson-Walker evolution on the largest scales as a function of redshift for both Einstein de-Sitter and Lambda CDM cosmologies. In both cases the effective energy density arising from
R. N. Manchester
Detection and study of gravitational waves from astrophysical sources is a major goal of current astrophysics. Ground-based laser-interferometer systems such as LIGO and VIRGO are sensitive to gravitational waves with frequencies of order 100 Hz, whereas space-based systems such as LISA are sensitive in the millihertz regime. Precise timing observations of a
Jonathan Engle, Roberto Pereira
Recently, two new spin-foam models have appeared in the literature, both motivated by a desire to modify the Barrett-Crane model in such a way that the imposition of certain second class constraints, called cross-simplicity constraints, are weakened. We refer to these two models as the FKLS model, and the flipped model. Both of these models are based on a re
Emma Y. Jin, Jing Qin, Christian M. Reidys
In this paper we prove a duality between $k$-noncrossing partitions over $[n]=\{1,...,n\}$ and $k$-noncrossing braids over $[n-1]$. This duality is derived directly via (generalized) vacillating tableaux which are in correspondence to tangled-diagrams \cite{Reidys:07vac}. We give a combinatorial interpretation of the bijection in terms of the contraction of
Willemien Visser
This paper presents a review of methods for collecting and analysing data on complex activities. Starting with methods developed for design, we examine the possibility to transpose them to other complex activities, especially activities referring to sensorial expertise. Résumé Ce texte présente une revue de méthodes pour recueillir et analyser des données su
Byeong Moon Kim, Ji Young Kim, Poo-Sung Park
We call a positive definite Hermitian lattice regular if it represents all integers which can be represented locally by the lattice. We investigate binary regular Hermitian lattices over imaginary quadratic fields $\mathbb{Q}(\sqrt{-m})$ and provide a complete list of the (normal) Hermitian lattices.
Byeong Moon Kim, Ji Young Kim, Poo-Sung Park
We will introduce a method to get all universal Hermitian lattices over imaginary quadratic fields over $\mathbb{Q}(\sqrt{-m})$ for all m. For each imaginary quadratic field $\mathbb{Q}(\sqrt{-m})$, we obtain a criterion on universality of Hermitian lattices: if a Hermitian lattice L represents 1, 2, 3, 5, 6, 7, 10, 13,14 and 15, then L is universal. We call
A. B. Balakin, H. Dehnen, A. E. Zayats
We establish a nonminimal Einstein-Yang-Mills-Higgs model, which contains six coupling parameters. First three parameters relate to the nonminimal coupling of non-Abelian gauge field and gravity field, two parameters describe the so-called derivative nonminimal coupling of scalar multiplet with gravity field, and the sixth parameter introduces the standard c
Toyohiro Tsurumaru, Alexandre Soujaeff, Shigeki Takeuchi
In this paper, for the decoy state method using a finite number of decoy light intensities, we present an improved upper and lower bounds for the asymptotic yield y_n for n-photon states. In particular if all the light intensities are less than or equal to one, they are not only a lower or upper bound, but in fact are the exact minimum or maximum.
Milan Krbalek
We investigate a microscopical structure in a chain of cars waiting at a red signal on signal-controlled crossroads. Presented is an one-dimensional space-continuous thermodynamical model leading to an excellent agreement with the data measured.Moreover, we demonstrate that an inter-vehicle spacing distribution disclosed in relevant traffic data agrees with
Sandra Leone
We report a selection of the most recent CDF and D0 results on top quark and W and Z boson properties, based on Tevatron Run 2 data. The large datasets of W and Z bosons allow a very precise measurement of the W mass and detailed studies of vector boson production and asymmetries. Associated production of vector boson pairs has been observed and cross sectio
Tommaso de Fernex, Mircea Mustata
Let T_n denote the set of log canonical thresholds of pairs (X,Y), with X a nonsingular variety of dimension n, and Y a nonempty closed subscheme of X. Using non-standard methods, we show that every limit of a decreasing sequence in T_n lies in T_{n-1}, proving in this setting a conjecture of Kollár. We also show that T_n is a closed subset in the set of rea
Yoshiharu Maeno
Methods to solve a node discovery problem for a social network are presented. Covert nodes refer to the nodes which are not observable directly. They transmit the influence and affect the resulting collaborative activities among the persons in a social network, but do not appear in the surveillance logs which record the participants of the collaborative acti
Measurement of CP Asymmetries and Branching Fractions in a Time-Dependent Dalitz Analysis of B^0-->(rho pi)^0 and a Constraint on the Quark Mixing Angle phi_2
hep-exThe Belle Collaboration, A. Kusaka, C. C. Wang
We present the results of a time-dependent Dalitz plot analysis of B0 --> pi+ pi- pi0 decays based on a 414/fb data sample that contains 449 x 10^6 BB pairs. The data was collected on the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e+e- collider. Combining our analysis with information on charged B decay modes, we perform a fu
Gerd Bergmann
The internal s-electron polarization in the ground state of a Friedel-Anderson and a Kondo impurity is calculated. The Wilson basis with exponentially fine energies close to the Fermi level is used and expressed in terms of free electron waves with linear energy-momentum dispersion. It is found that in the singlet state the magnetic moment of the d-electron
Herbert M Sauro, Brian Ingalls
Interconvertible enzyme cascades, exemplified by the mitogen activated protein kinase (MAPK) cascade, are a frequent mechanism in signal transduction pathways. There has been much speculation as to the role of these pathways, and how their structure is related to their function. A common conclusion is that the cascades serve to amplify biochemical signals so
Rate-Constrained Wireless Networks with Fading Channels: Interference-Limited and Noise-Limited Regimes
cs.ITMasoud Ebrahimi, Amir K. Khandani
A network of $n$ wireless communication links is considered in a Rayleigh fading environment. It is assumed that each link can be active and transmit with a constant power $P$ or remain silent. The objective is to maximize the number of active links such that each active link can transmit with a constant rate $λ$. An upper bound is derived that shows the num
Searching for new thermally emitting isolated neutron stars in the 2XMMp catalogue - Discovery of a promising candidate
astro-phAdriana M. Pires, Christian Motch
The group of 7 thermally emitting and radio-quiet isolated neutron stars (INSs) discovered by ROSAT constitutes a nearby population which locally appears to be as numerous as that of the classical radio pulsars. So far, attempts to enlarge this particular group of INSs finding more remote objects failed to confirm any candidate. We found in the 2XMMp catalog
H. M. Aktulga, I. Kontoyiannis, L. A. Lyznik, L. Szpankowski
Questions of understanding and quantifying the representation and amount of information in organisms have become a central part of biological research, as they potentially hold the key to fundamental advances. In this paper, we demonstrate the use of information-theoretic tools for the task of identifying segments of biomolecules (DNA or RNA) that are statis
Cosmological redshift and nonlinear electrodynamics propagation of photons from distant sources
astro-phHerman J. Mosquera Cuesta, Jose M. Salim, M. Novello
By-now photons are the unique universal messengers. Cosmological sources like far-away galaxies or quasars are well-known light-emitters. Here we demonstrate that the nonlinear electrodynamics (NLED) description of photon propagation through the weak background intergalactic magnetic fields modifies in a fundamental way the cosmological redshift that a direc
U. O. Yilmaz, G. Turan
The general analysis of the rare Bc->D^*_s l^+ l^- decay is presented by using the most general, model independent effective Hamiltonian. The dependencies of the branching ratios, longitudinal, normal and transversal polarization asymmetries for l^- and the combined asymmetries for l^- and l^+ on the new Wilson coefficients are investigated. Our analysis sho
Pierre Berger
This manuscript complements the Hirsch-Pugh-Shub (HPS) theory on persistence of normally hyperbolic laminations and the theorem of Robinson on the structural stability of diffeomorphisms that satisfy Axiom A and the strong transversality condition (SA). We generalize these results by introducing a geometric object: the stratification of laminations. It is a
Olivier Mousis, Yann Alibert, Daniel Hestroffer, Ulysse Marboeuf
We propose a scenario for the formation of the Main Belt in which asteroids incorporated icy particles formed in the outer Solar Nebula. We calculate the composition of icy planetesimals formed beyond a heliocentric distance of 5 AU in the nebula by assuming that the abundances of all elements, in particular that of oxygen, are solar. As a result, we show th
F. Cardone, R. Mignani, A. Petrucci
We show that cavitation of a solution of thorium-228 in water induces its transformation at a rate 10000 times faster than the natural radioactive decay would do. This result agrees with the alteration of the secular equilibrium of thorium-234 obtained by a Russian team via explosion of titanium foils in water and solutions. These evidences further support s
A. Schuessler, D. Zeppenfeld
For MSSM phenomenology, soft SUSY breaking dimension-three operators are important, in particular the couplings between Higgs bosons and squarks. In scattering processes, perturbative unitarity is violated at modest center-of-mass energy if these couplings are much larger than the masses of the scalar particles involved. Assuming perturbative unitarity, cons
C. Denson Hill, Mauro Nacinovich
There is an intrinsic notion of what it means for a contact manifold to be the smooth boundary of a Stein manifold. The same concept has another more extrinsic formulation, which is often used as a convenient working hypothesis. We give a simple proof that the two are equivalent. Moreover it is shown that, even though a border always exists, it's germ is
S. Valenti, S. Benetti, E. Cappellaro, F. Patat
The results of a world-wide coordinated observational campaign on the broad-lined Type Ic SN 2003jd are presented. In total, 74 photometric data points and 26 spectra were collected using 11 different telescopes. SN 2003jd is one of the most luminous SN Ic ever observed. A comparison with other Type Ic supernovae (SNe Ic) confirms that SN 2003jd represents a
Adam Amara, Alexandre Refregier
We describe a method for computing the biases that systematic signals introduce in parameter estimation using a simple extension of the Fisher matrix formalism. This allows us to calculate the offset of the best fit parameters relative to the fiducial model, in addition to the usual statistical error ellipse. As an application, we study the impact that resid
Sergi Elizalde
In this paper we give a bijection between the class of permutations that can be drawn on an X-shape and a certain set of permutations that appears in [Knuth] in connection to sorting algorithms. A natural generalization of this set leads us to the definition of almost-increasing permutations, which is a one-parameter family of permutations that can be charac
C. Denson Hill, Mauro Nacinovich
Let $M$ be a smooth compact $CR$ manifold of $CR$ dimension $n$ and $CR$ codimension $k$, which has a certain local extension property $E$. In particular, if $M$ is pseudoconcave, it has property $E$. Then the field $\Cal K(M)$ of $CR$ meromorphic functions on $M$ has transcendence degree $d$, with $d\leq n+k$. If $f_1, f_2, \hdots , f_d$ is a maximal set of
D. E. Groh, J. S. Pinter, P. F. Mantica, T. J. Mertzimekis
Intermediate-energy heavy-ion collisions can produce a spin polarization of the projectile-like species. Spin polarization has been observed for both nucleon removal and nucleon pickup processes. Qualitative agreement with measured spin polarization as a function of the momentum of the projectile-like fragment is found in a kinematical model that considers c
Newly Discovered Cataclysmic Variables from the INT/WFC Photometric H alpha Survey of the Northern Galactic Plane
astro-phA. R. Witham, C. Knigge, A. Aungwerojwit, J. E. Drew
We report the discovery of 11 new cataclysmic variable (CV) candidates by the Isaac Newton Telescope (INT) Photometric H alpha Survey of the northern Galactic plane (IPHAS). Three of the systems have been the subject of further follow-up observations. For the CV candidates IPHAS J013031.90+622132.4 and IPHAS J051814.34+294113.2, time-resolved optical spectro
R. Michael Rich, Christian Howard, David B. Reitzel, HongSheng Zhao
We present recent results from a Keck study of the composition of the Galactic bulge, as well as results from the bulge Bulge Radial Velocity Assay (BRAVA). Culminating a 10 year investigation, Fulbright, McWilliam, & Rich (2006, 2007) solved the problem of deriving the iron abundance in the Galactic bulge, and find enhanced alpha element abundances, consist
Decomposable Subspaces, Linear Sections of Grassmann Varieties, and Higher Weights of Grassmann Codes
math.AGSudhir R. Ghorpade, Arunkumar R. Patil, Harish K. Pillai
Given a homogeneous component of an exterior algebra, we characterize those subspaces in which every nonzero element is decomposable. In geometric terms, this corresponds to characterizing the projective linear subvarieties of the Grassmann variety with its Plucker embedding. When the base field is finite, we consider the more general question of determining
David Delphenich
It is demonstrated that when the bundle of 2-forms on a four-dimensional manifold M admits an almost-complex structure any choice of "real + imaginary" subspace decomposition of the bundle defines a conjugation map, as well as a Hermitian structure for the bundle. When the almost-complex structure comes from a linear electromagnetic constitutive law,
M. O. Ribas, F. P. Devecchi, G. M. Kremer
A model for the Universe is proposed whose constituents are: (a) a dark energy field modeled by a fermionic field non-minimally coupled with the gravitational field, (b) a matter field which consists of pressureless baryonic and dark matter fields and (c) a field which represents the radiation and the neutrinos. The coupled system of Dirac's equations an
H. Isliker
The combined Continuous Time Random Walk (CTRW) in position and momentum space is introduced, in the form of two coupled integral equations that describe the evolution of the probability distribution for finding a particle at a certain position and with a certain momentum as a function of time. The integral equations are solved numerically with a pseudospect
Dmitriy M. Belov, Chris M. Hull, Ruben Minasian
We revisit sigma models on target spaces given by a principal torus fibration $X\to M$, and show how treating the 2-form B as a gerbe connection captures the gauging obstructions and the global constraints on the T-duality. We show that a gerbe connection on X, which is invariant with respect to the torus action, yields an affine double torus fibration Y ove
K. Huebner, F. Karsch, O. Kaczmarek, O. Vogt
We study the free energy of static three quark systems in singlet, octet, decuplet and average color channels in the quenched approximation and in 2-flavor QCD at finite temperature. We show that in the high temperature phase singlet and decuplet free energies of three quark systems are well described by the sum of the free energies of three diquark systems
Gusztav Morvai, Benjamin Weiss
The forecasting problem for a stationary and ergodic binary time series $\{X_n\}_{n=0}^{\infty}$ is to estimate the probability that $X_{n+1}=1$ based on the observations $X_i$, $0\le i\le n$ without prior knowledge of the distribution of the process $\{X_n\}$. It is known that this is not possible if one estimates at all values of $n$. We present a simple p
Hector Giacomini, Jaume Gine, Maite Grau
Our purpose in this paper is to study when a planar differential system polynomial in one variable linearizes in the sense that it has an inverse integrating factor which can be constructed by means of the solutions of linear differential equations. We give several families of differential systems which illustrate how the integrability of the system passes t
Kord Eickmeyer, Peter Huggins, Lior Pachter, Ruriko Yoshida
The popular neighbor-joining (NJ) algorithm used in phylogenetics is a greedy algorithm for finding the balanced minimum evolution (BME) tree associated to a dissimilarity map. From this point of view, NJ is ``optimal'' when the algorithm outputs the tree which minimizes the balanced minimum evolution criterion. We use the fact that the NJ tree topol
I. Kravchenko
We present a search for neutral supersymmetric Higgs bosons decaying to tau+tau- pairs produced in ppbar collisions at sqrt{s}=1.96 TeV. The data have been collected with the CDF II and D0 detectors at the Tevatron collider at Fermilab (1 fb^-1 of integrated luminosity per experiment). No significant excess above the standard model backgrounds is observed. W
Ricardo Coelho, Peter Richmond, Stefan Hutzler, Brian Lucey
We study correlations of a set of stocks selected from both the New York and London stock exchanges. Results are displayed using both Random Matrix Theory approach and the graphical visualisation of the Minimal Spanning Tree. For the set of stocks we study, cross correlations between markets do not mix the markets significantly. Geographical differences seem
M. de J. Anguiano-Galicia, A. Bashir, A. Raya
We solve Dirac equation in the presence of a constant magnetic field in (3+1)- and (2+1)-dimensions. Quantizing the fermion field, we calculate $\barψ ψ$-condensate from first principles for parity conserving and violating Lagrangians for arbitrary field strength. We make comparison with the results already known in the literature for some particular cases a
Comment on: Direct space-time observation of pulse tunneling in an electromagnetic band gap, S.Doiron,A.Hache,H.Winful
quant-phG. Nimtz, A. A. Stahlhofen
The title of this article is misleading. The authors have investigated a resonator but not a tunneling barrier see also Refs.\cite{Winful2} The measured superluminal group velocity and discussed is that studied on a Lorentz-Lorenz oscillator by Sommerfeld and Brillouin a hundred years ago \cite{Brillouin}. It is similar to the faster than light experiment by
Arvind Ayyer
We show that the half-perimeter generating functions for the number of Wicketed and Gated Ferrers diagrams is algebraic. Furthermore, the generating function of the Wicketed Ferrers diagrams is closely related to the generating function of the Catalan numbers. The methodology of the experimentation as well as the proof is the umbral transfer matrix method.
Marco Fattori, Chiara D'Errico, Giacomo Roati, Matteo Zaccanti
We demonstrate the operation of an atom interferometer based on a weakly interacting Bose-Einstein condensate. We strongly reduce the interaction induced decoherence that usually limits interferometers based on trapped condensates by tuning the s-wave scattering length almost to zero via a magnetic Feshbach resonance. We employ a $^{39}$K condensate trapped
Manfred Kufleitner
We show that for every homomorphism $Γ^+ \to S$ where $S$ is a finite semigroup there exists a factorization forest of height $\leq 3 \abs{S}$. The proof is based on Green's relations.
Testing the nonlinearity of the BVIcJHKs period-luminosity relations for the Large Magellanic Cloud Cepheids
astro-phC. Ngeow, S. Kanbur, A. Nanthakumar
A number of recent works have suggested that the period-luminosity (PL) relation for the Large Magellanic Cloud (LMC) Cepheids exhibits a controversial nonlinear feature with a break period at 10 days. Therefore, the aim of this Research Note is to test the linearity/nonlinearity of the PL relations for the LMC Cepheids in BVIcJHKs band, as well as in the We
Nils Krumnack
We present the results of searches by the CDF and DØ Collaborations for Higgs boson production in $p\bar{p}$ collisions at $\sqrt{s}=1.96 {\rm TeV}$. The searches are performed in the $WW^*$ channel with $1 {\rm fb}^{-1}$ of data. In the absence of signal the results are used to set a limit on the Higgs production cross section times branching ratio.
Agnes Mocsy, Peter Petreczky
We present a detailed investigation of the quark mass-dependence of charmonium correlators in Euclidean-time obtained using a potential model, as well as the comparison with results on isotropic lattice calculations performed at several lattice spacings.
Constraining Spiral Structure Parameters through Galactic Pencil-beam and Large-scale Radial Velocity Surveys
astro-phI. Minchev, A. Quillen
We investigate the effect of spiral structure on the Galactic disk as viewed by pencil beams centered on the Sun, relevant to upcoming surveys such as ARGOS, SEGUE, and GAIA. We create synthetic Galactic maps which we call Pencil Beam Maps (PBMs) of the following observables: line-of-sight velocities, the corresponding velocity dispersion, and the stellar nu
Gilbert Moultaka
We address the question of gravitino dark matter in the context of gauge mediated supersymmetry breaking models. A special emphasis is put on the role played by the MSSM singlet messenger in the case of SO(10) grand unification.
Vincenzo Chiochia
The CMS experiment at the LHC includes a hybrid silicon pixel detector for the reconstruction of charged tracks and of the interaction vertices. The detector is made of three barrel layers and two disks at each end of the barrel. Detector modules consist of thin, segmented silicon sensors with highly integrated readout chips connected by the bump bonding tec