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Can rigidly rotating polytropes be sources of the Kerr metric?Sep 07 2007We use a recent result by Cabezas et al. to build up an approximate solution to the gravitational field created by a rigidly rotating polytrope. We solve the linearized Einstein equations inside and outside the surface of zero pressure including second-order ... More

Traces of exomoons in computed flux and polarization phase curves of starlight reflected by exoplanetsJul 26 2018Context: Detecting moons around exoplanets is a major goal of current and future observatories. Moons are suspected to influence rocky exoplanet habitability, and gaseous exoplanets in stellar habitable zones could harbour abundant and diverse moons to ... More

PyMieDAP: a Python--Fortran tool to compute fluxes and polarization signals of (exo)planetsApr 23 2018PyMieDAP (the Python Mie Doubling-Adding Programme) is a Python--based tool for computing the total, linearly, and circularly polarized fluxes of incident unpolarized sun- or starlight that is reflected by, respectively, Solar System planets or moons, ... More

Covariation representations for Hermitian Lévy process ensembles of free infinitely divisible distributionsJul 16 2012Dec 14 2012It is known that the so-called Bercovici-Pata bijection can be explained in terms of certain Hermitian random matrix ensembles $(M_{d})_{d\geq1}$ whose asymptotic spectral distributions are free infinitely divisible. We investigate Hermitian L\'{e}vy ... More

Comparing metrics at large: harmonic vs quo-harmonic coordinatesApr 05 2001To compare two space-times on large domains, and in particular the global structure of their manifolds, requires using identical frames of reference and associated coordinate conditions. In this paper we use and compare two classes of time-like congruences ... More

Barrier efficiency of sponge-like La2Zr2O7 buffer layers for YBCO-coated conductorsMar 30 2011Solution derived La2Zr2O7 films have drawn much attention for potential applications as thermal barriers or low-cost buffer layers for coated conductor technology. Annealing and coating parameters strongly affect the microstructure of La2Zr2O7, but different ... More

Charmed hadrons in nuclear mediumDec 15 2009We study the properties of charmed hadrons in dense matter within a coupled-channel approach which accounts for Pauli blocking effects and meson self-energies in a self-consistent manner. We analyze the behaviour in this dense environment of dynamically-generated ... More

Model Selection for Pion PhotoproductionOct 24 2016Dec 23 2016Partial-wave analysis of meson and photon-induced reactions is needed to enable the comparison of many theoretical approaches to data. In both energy-dependent and independent parametrizations of partial waves, the selection of the model amplitude is ... More

Effect of solute content and temperature on the deformation mechanisms and critical resolved shear stress in Mg-Al and Mg-Zn alloysMar 20 2019The influence of solute atoms (Al and Zn) on the deformation mechanisms and the critical resolved shear stress for basal slip in Mg alloys at 298 K and 373 K was ascertained by micropillar compression tests in combination with high-throughput processing ... More

Random Schrödinger Operators on discrete structuresOct 06 2017Jul 29 2018The Anderson model serves to study the absence of wave propagation in a medium in the presence of impurities, and is one of the most studied examples in the theory of quantum disordered systems. In these notes we give a review of the spectral and dynamical ... More

Ultraviolet Spectropolarimetry as a Tool for Understanding the Diversity of Exoplanetary AtmospheresMar 14 2019The polarization state of starlight reflected by a planetary atmosphere uniquely reveals coverage, particle size, and composition of aerosols as well as changing cloud patterns. It is not possible to obtain a comparable level of detailed from flux-only ... More

Ultraviolet Spectropolarimetry as a Tool for Understanding the Diversity of Exoplanetary AtmospheresMar 14 2019Mar 15 2019The polarization state of starlight reflected by a planetary atmosphere uniquely reveals coverage, particle size, and composition of aerosols as well as changing cloud patterns. It is not possible to obtain a comparable level of detailed from flux-only ... More

Best prediction under a nested error model with log transformationApr 22 2014In regression models involving economic variables such as income, log transformation is typically taken to achieve approximate normality and stabilize the variance. However, often the interest is predicting individual values or means of the variable in ... More

Model Predictive Control of Voltage Source Converter in a HVDC SystemApr 13 2017Model Predictive Control (MPC) method is a class of advanced control techniques most widely applied in industry. The major advantages of the MPC are its straightforward procedure which can be applied for both linear and nonlinear system. This paper proposes ... More

Strange and charm mesons at FAIRNov 11 2009We study the properties of strange and charm mesons in hot and dense matter within a self-consistent coupled-channel approach for the experimental conditions of density and temperature expected for the CBM experiment at FAIR/GSI. The in-medium solution ... More

Non-parametric Impedance based Stability and Controller Bandwidth Extraction from Impedance Measurements of HVDC-connected Wind FarmsApr 16 2017Impedance measurements have been widely used with the Nyquist plot to estimate the stability of interconnected power systems. Being a black-box method for equivalent and aggregated impedance estimation, its use for the identification of sub-components ... More

Paracontact metric structures on the unit tangent sphere bundleSep 17 2013Starting from $g$-natural pseudo-Riemannian metrics of suitable signature on the unit tangent sphere bundle $T_1 M$ of a Riemannian manifold $(M,\langle,\rangle)$, we construct a family of paracontact metric structures. We prove that this class of paracontact ... More

The curvature tensor of almost cosymplectic and almost Kenmotsu (κ,μ,ν)-spacesJan 26 2012Feb 10 2012We study the Riemann curvature tensor of (\kappa,\mu,\nu)-spaces when they have almost cosymplectic and almost Kenmotsu structures, giving its writing explicitly. This leads to the definition and study of a natural generalisation of the contact metric ... More

Associative and Lie algebras of quotientsSep 22 2005In this paper we examine how the notion of algebra of quotients for Lie algebras ties up with the corresponding well-known concept in the associative case. Specifically, we completely characterize when a Lie algebra $Q$ is an algebra of quotients of a ... More

Sub-Riemannian geodesics and heat operator on odd dimensional spheresAug 31 2010In this article we study the sub-Riemannian geometry of the spheres $S^{2n+1}$ and $S^{4n+3}$, arising from the principal $S^1-$bundle structure defined by the Hopf map and the principal $S^3-$bundle structure given by the quaternionic Hopf map respectively. ... More

Geometric conditions for the existence of an intrinsic rollingNov 03 2011We give a complete answer to the question of when two curves in two different Riemannian manifolds can be seen as trajectories of rolling one manifold on the other without twisting or slipping. We show that up to technical hypotheses, a rolling along ... More

A rapid and well-conditioned algorithm for the Helmholtz--Hodge decomposition of vector fields on the sphereSep 12 2018A rapid algorithm is derived for the Helmholtz--Hodge decomposition on the surface of the sphere in spherical coordinates. The algorithm uncouples modes of spherical harmonics with different absolute order, writes the conversion as barely-overdetermined ... More

Scale-free unique continuation estimates and applications to random Schrödinger operatorsOct 20 2012We prove a unique continuation principle or uncertainty relation valid for Schr\"odinger operator eigenfunctions, or more generally solutions of a Schr\"odinger inequality, on cubes of side $L\in 2\NN+1$. It establishes an equi-distribution property of ... More

Optimal Regular Expressions for PermutationsDec 15 2018The permutation language $P_n$ consists of all words that are permutations of a fixed alphabet of size $n$. Using divide-and-conquer, we construct a regular expression $R_n$ that specifies $P_n$. We then give explicit bounds for the length of $R_n$, which ... More

Maximum and minimum nullity of a tree degree sequenceJun 06 2018The nullity of a graph is the multiplicity of the eigenvalue zero in its adjacency spectrum. In this paper, we give a closed formula for the minimum and maximum nullity among trees with the same degree sequence, using the notion of matching number and ... More

The Tracy-Widom distribution is not infinitely divisibleJan 12 2016The classical infinite divisibility of distributions related to eigenvalues of some random matrix ensembles is investigated. It is proved that the $\beta$-Tracy-Widom distribution, which is the limiting distribution of the largest eigenvalue of a $\beta$-Hermite ... More

Submersions and curves of constant geodesic curvatureJul 17 2017Considering Riemannian submersions, we find necessary and sufficient conditions for when sub-Riemannian normal geodesics project to curves of constant first geodesic curvature or constant first and vanishing second geodesic curvatures. We describe a canonical ... More

A classification of totally geodesic and totally umbilical Legendrian submanifolds of $(κ,μ)$-spacesNov 14 2016Feb 07 2019We present classifications of totally geodesic and totally umbilical Legendrian submanifolds of $(\kappa,\mu)$-spaces with Boeckx invariant $I \leq -1$. In particular, we prove that such submanifolds must be, up to local isometries, among the examples ... More

An automorphic approach to Darmon pointsSep 20 2017We give archimedean and non-archimedean constructions of Darmon points on modular abelian varieties attached to automorphic forms over arbitrary number fields and possibly non-trivial central character. An effort is made to present a unifying point of ... More

Localization length versus level repulsion in 1-D driven disordered quantum wiresNov 02 2017We study the level repulsion and its relationship with the localization length in a disordered one-dimensional quantum wire excited with monochromatic linearly polarized light and described by the Anderson-Floquet model. In the high frequency regime, ... More

Interactive Data Exploration with Smart Drill-DownDec 01 2014Dec 19 2016We present {\em smart drill-down}, an operator for interactively exploring a relational table to discover and summarize "interesting" groups of tuples. Each group of tuples is described by a {\em rule}. For instance, the rule $(a, b, \star, 1000)$ tells ... More

Suggesting Cooking Recipes Through Simulation and Bayesian OptimizationNov 09 2018Cooking typically involves a plethora of decisions about ingredients and tools that need to be chosen in order to write a good cooking recipe. Cooking can be modelled in an optimization framework, as it involves a search space of ingredients, kitchen ... More

Unbiased Cosmological Parameter Estimation from Emission Line Surveys with InterlopersNov 16 2018Mar 08 2019The galaxy catalogs generated from low-resolution emission line surveys often contain both foreground and background interlopers due to line misidentification, which can bias the cosmological parameter estimation. In this paper, we present a method for ... More

The rolling problem: overview and challengesJan 27 2013In the present paper we give a historical account -ranging from classical to modern results- of the problem of rolling two Riemannian manifolds one on the other, with the restrictions that they cannot instantaneously slip or spin one with respect to the ... More

Electron inelastic mean free paths in condensed matter down to a few electronvoltsJul 31 2018A method is reported for a simple, yet reliable, calculation of electron inelastic mean free paths in condensed phase insulating and conducting materials, from the very low energies of hot electrons up to the high energies characteristic of electron beams. ... More

Comments on the dispersion relation method to vector-vector interactionMar 12 2019We study in detail the method proposed recently to study the vector-vector interaction using the $N/D$ method and dispersion relations, which concludes that, while for $J=0$, one finds bound states, in the case of $J=2$, where the interaction is also ... More

Quantum Pontryagin Principle under Continuous Measurements and FeedbackJul 12 2018In this note we develop the theory of the quantum Pontryagin principle for continuous measurements and feedback. The analysis is carried out under the assumption of compatible events in the output channel. The plant is a quantum system, which generally ... More

S-treesSep 12 2017In this paper two new graph operations are introduced, and with them the S-trees are studied in depth. This allows to find \(\{-1,0,1\}\)-basis for all the fundamental subspaces of the adjacency matrix of any tree, and to understand in detail the matching ... More

Surface states in topological semimetal slab geometriesOct 24 2018Weyl semimetals are topological materials with protected Weyl nodes in the band structure. In these materials the surface states form open curves at the Fermi surface, Fermi arcs in Weyl semimetals and drumhead states of nodal-line semimetals. In this ... More

Infrared spectroscopy of eruptive variable protostars from VVVFeb 19 2016In the first part of this study (Paper I) we detected a large population of highly variable Young Stellar Objects (YSOs) in the Vista Variables in the Via Lactea (VVV) survey, typically with Class I or flat spectrum SEDs and a variety of light curve types. ... More

Soft spin dipole giant resonances in 40CaAug 16 2013High resolution experimental data has been obtained for the 40,42,44,48Ca(3He,t)Sc charge exchange reaction at 420 MeV beam energy, which favors the spin-isospin excitations. The measured angular distributions were analyzed for each state separately, ... More

A population of eruptive variable protostars in VVVFeb 19 2016We present the results of a search for high amplitude infrared variable stars in 119 sq. deg of the Galactic midplane covered by the VVV survey. We find 816 variables with $\Delta K_{\rm s}>1$mag in the 2010-2012 data, almost all of which are new discoveries. ... More

An intrinsic formulation of the rolling manifolds problemAug 11 2010We present an intrinsic formulation of the kinematic problem of two $n-$dimensional manifolds rolling one on another without twisting or slipping. We determine the configuration space of the system, which is an $\frac{n(n+3)}2-$dimensional manifold. The ... More

Wahlquist's metric versus an approximate solution with the same equation of stateJan 21 2013May 10 2013We compare an approximation of the singularity-free Wahlquist exact solution with a stationary and axisymmetric metric for a rigidly rotating perfect fluid with the equation of state $\mu + 3p= \mu_0$, a sub-case of a global approximate metric obtained ... More

A modified sequence domain impedance definition and its equivalence to the dq-domain impedance definition for the stability analysis of AC power electronic systemsApr 28 2016Representations of AC power systems by frequency dependent impedance equivalents is an emerging technique in the dynamic analysis of power systems including power electronic converters. The technique has been applied for decades in DC-power systems, and ... More

PyCaMa: Python for cash managementFeb 16 2017Feb 18 2017Selecting the best policy to keep the balance between what a company holds in cash and what is placed in alternative investments is by no means straightforward. We here introduce PyCaMa, a Python module for multiobjective cash management based on linear ... More

Observation of the 2$^+$ isomer in $^{52}$CoMay 27 2016Oct 10 2016We report the first observation of the 2$^+$ isomer in $^{52}$Co, produced in the $\beta$ decay of the 0$^+$, $^{52}$Ni ground state. We have observed three $\gamma$-rays at 849, 1910, and 5185 keV characterizing the $\beta$ de-excitation of the isomer. ... More

Beta Decay Of Exotic Tz = -1 And Tz = -2 NucleiJan 31 2013The half-lives of the Tz = -2, 56Zn and Tz = -1, 58Zn isotopes and other nuclei were measured in a {\beta}-decay experiment at GANIL. The energy levels populated by the 56Zn {\beta} decay were determined. The 56Zn results are compared with the results ... More

High-precision Astrometric Millimeter Very Long Baseline Interferometry Using a New Method for Multi-Frequency CalibrationDec 09 2016In this paper we describe a new approach for mm-VLBI calibration that provides bona-fide astrometric alignment of the mm-wavelength images from a single source, for the measurement of frequency dependent effects, such as `core-shifts' near the black hole ... More

A $\{-1,0,1\}$- and sparsest basis for the null space of a forest in optimal timeOct 04 2017Given a matrix, the Null Space Problem asks for a basis of its null space having the fewest nonzeros. This problem is known to be NP-complete and even hard to approximate. The null space of a forest is the null space of its adjacency matrix. Sander and ... More

A Gaussian Variational Approach to cMERA for Interacting FieldsDec 07 2016Jun 05 2018We use the Gaussian variational principle to apply cMERA to interacting quantum field theories in arbitrary spacetime dimensions. By establishing a correspondence between the first two terms in the variational expansion and the Gaussian Effective Potential, ... More

Generalized (κ,μ)-space formsDec 14 2008Feb 06 2012Generalized (\kappa ,\mu)-space forms are introduced and studied. We examine in depth the contact metric case and present examples for all possible dimensions. We also analyse the trans-Sasakian case.

Characterization of the metal-insulator transport transition for the two-particle Anderson modelApr 12 2016Feb 10 2017We extend to the two-particle Anderson model the characterization of the metal-insulator transport transition obtained in the one-particle setting by Germinet and Klein. We show that, for any fixed number of particles, the slow spreading of wave packets ... More

Sigma resonance parameters from a $N_f=2$ lattice QCD simulationApr 26 2018Jul 29 2018In this work we present the analysis of the energy spectrum from a recent two-flavor ($N_f=2$) lattice QCD calculation for pion-pion scattering in the scalar, isoscalar channel (the $\sigma$-meson). The lattice simulation was performed for two quark masses ... More

Rho resonance parameters from lattice QCDMay 12 2016Jul 21 2016We perform a high-precision calculation of the phase shifts for $\pi$-$\pi$ scattering in the I = 1, J = 1 channel in the elastic region using elongated lattices with two mass-degenerate quark favors ($N_f = 2$). We extract the $\rho$ resonance parameters ... More

The DAMIC dark matter experimentOct 07 2015The DAMIC (Dark Matter in CCDs) experiment uses high resistivity, scientific grade CCDs to search for dark matter. The CCD's low electronic noise allows an unprecedently low energy threshold of a few tens of eV that make it possible to detect silicon ... More

Measurement of radioactive contamination in the high-resistivity silicon CCDs of the DAMIC experimentJun 08 2015Jul 09 2015We present measurements of radioactive contamination in the high-resistivity silicon charge-coupled devices (CCDs) used by the DAMIC experiment to search for dark matter particles. Novel analysis methods, which exploit the unique spatial resolution of ... More

The Dynamics and Distribution of Angular Momentum in HiZELS Star-Forming Galaxies at z = 0.8 - 3.3Mar 12 2019We present adaptive optics assisted integral field spectroscopy of 34 star-forming galaxies at $z$ = 0.8-3.3 selected from the HiZELS narrow-band survey. We measure the kinematics of the ionised interstellar medium on $\sim$1 kpc scales, and show that ... More

Sasaki-Einstein and paraSasaki-Einstein metrics from (κ,μ)-structuresSep 28 2011Jun 16 2013We prove that any non-Sasakian contact metric (\kappa,\mu)-space admits a canonical \eta-Einstein Sasakian or \eta-Einstein paraSasakian metric. An explicit expression for the curvature tensor fields of those metrics is given and we find the values of ... More

Role of the strange quark in the rho(770) mesonNov 14 2016Recently, the GWU lattice group has evaluated high-precision phase-shift data for $\pi\pi$ scattering in the $I = 1$, $J = 1$ channel. Unitary Chiral Perturbation Theory describes these data well around the resonance region and for different pion masses. ... More

Chemical Vapor Deposition Growth of Boron-Carbon-Nitrogen layers from Methylamine Borane Thermolysis ProductsFeb 20 2019This work investigates the growth of B-C-N layers by chemical vapor deposition using methylamine borane (MeAB) as single-source precursor. MeAB has been synthesized and characterized, paying particular attention to the analysis of its thermolysis products, ... More

VALES V: A kinematic analysis of the molecular gas content in $H$-ATLAS galaxies at $z\sim0.03-0.35$ using ALMASep 27 2018We present Atacama Large Millimeter/submillimeter Array (ALMA) resolved observations of molecular gas in galaxies up to $z=0.35$ to characterise the role of global galactic dynamics on the global interstellar medium (ISM) properties. These observations ... More

Rotating black holes in a Randall-Sundrum brane with a cosmological constantNov 12 2012Jan 11 2013In this work we have constructed axially symmetric vacuum solutions of the gravitational field equations in a Randall-Sundrum brane. A non-null effective cosmological constant is considered, and asymptotically de Sitter and anti-de Sitter spacetimes are ... More

Diffusion in infinite and semi-infinite lattices with long-range couplingDec 30 2011We prove that for a one-dimensional infinite lattice, with long-range coupling among sites, the diffusion of an initial delta-like pulse in the bulk, is ballistic at all times. We obtain a closed-form expression for the mean square displacement (MSD) ... More

An approximate global stationary axisymmetric solution of the Einstein equationsJul 05 2004Aug 30 2004In this work we present an approximate solution of the Einstein equations describing a global model for the gravitational field generated by a bounded, self-gravitating stationary and axisymmetric body rotating rigidly with constant angular velocity.

A relativistic generalisation of rigid motionsMar 23 2011Radar-holonomic congruences of wordlines are proposed as a weaker substitute for the too restrictive class of Born-rigid motions. The definition is expressed as a set of differential equations. Integrability conditions and Cauchy data are studied. We ... More

Two-flavor Simulations of the $ρ(770)$ and the Role of the $K\bar K$ ChannelMay 16 2016Aug 20 2016The $\rho (770)$ meson is the most extensively studied resonance in lattice QCD simulations in two ($N_f=2$) and three ($N_f=2+1$) flavor formulations. We analyze $N_f=2$ lattice scattering data using unitarized Chiral Perturbation Theory, allowing not ... More

Simrank++: Query rewriting through link analysis of the click graphDec 04 2007We focus on the problem of query rewriting for sponsored search. We base rewrites on a historical click graph that records the ads that have been clicked on in response to past user queries. Given a query q, we first consider Simrank as a way to identify ... More

The curvature tensor of (\ka,μ,ν)-contact metric manifoldsSep 28 2011We study the Riemann curvature tensor of (\kappa,\mu,\nu)-contact metric manifolds, which we prove to be completely determined in dimension 3, and we observe how it is affected by D_a-homothetic deformations. This prompts the definition and study of generalized ... More

Perils of Zero-Interaction Security in the Internet of ThingsJan 22 2019Feb 22 2019The Internet of Things (IoT) demands authentication systems which can provide both security and usability. Recent research utilizes the rich sensing capabilities of smart devices to build security schemes operating without human interaction, such as zero-interaction ... More

Extraction of isoscalar $ππ$ phase-shifts from lattice QCDMar 07 2018We conduct a two-flavor ($N_f=2$) lattice QCD calculation of the elastic phase-shifts for pion-pion scattering in the scalar, isoscalar channel (the $\sigma$-meson). The calculation is performed for two quark masses corresponding to a pion mass of $315\text{ ... More

First results from the Very Small Array -- II. Observations of the CMBMay 22 2002Dec 20 2002We have observed the cosmic microwave background temperature fluctuations in eight fields covering three separated areas of sky with the Very Small Array at 34 GHz. A total area of 101 square degrees has been imaged, with sensitivity on angular scales ... More

On the motion of a classical charged particleNov 03 2004We show that the Lorentz-Dirac equation is not an unavoidable consequence of energy-momentum conservation for a point charge. What follows solely from conservation laws is a less restrictive equation already obtained by Honig and Szamosi. The latter is ... More

Spectral statistics of molecular resonances in erbium isotopes: How chaotic are they?Jun 26 2015Oct 06 2015We perform a comprehensive analysis of the spectral statistics of the molecular resonances in $^{166}$Er and $^{168}$Er observed in recent ultracold collision experiments [Frisch et al., Nature {\bf 507}, 475 (2014)] with the aim of determining the chaoticity ... More

Complexity Functionals and Complexity Growth Limits in Continuous MERA CircuitsMar 06 2018Jun 27 2018Using the path integral associated to a cMERA tensor network, we provide an operational definition for the complexity of a cMERA circuit/state which is relevant to investigate the complexity of states in quantum field theory. In this framework, it is ... More

Wormholes in de Sitter branesApr 05 2012Aug 02 2012In this work we present a class of geometries which describes wormholes in a Randall-Sundrum brane model, focusing on de Sitter backgrounds. Maximal extensions of the solutions are constructed and their causal structures are discussed. A perturbative ... More

Dimensional Crossover for the Bose -- Einstein Condensation of an Ideal Bose GasApr 10 1997We study an ideal Bose gas of N atoms contained in a box formed by two identical planar and parallel surfaces S, enclosed by a mantle of height a perpendicular to them. Calling r0 the mean atomic distance, we assume S >> r0^2 while a may be comparable ... More

Random matrix models of stochastic integral type for free infinitely divisible distributionsMay 20 2010Jan 19 2012The Bercovici-Pata bijection maps the set of classical infinitely divisible distributions to the set of free infinitely divisible distributions. The purpose of this work is to study random matrix models for free infinitely divisible distributions under ... More

First results from the Very Small Array -- IV. Cosmological parameter estimationMay 22 2002May 09 2003We investigate the constraints on basic cosmological parameters set by the first compact-configuration observations of the Very Small Array (VSA), and other cosmological data sets, in the standard inflationary LambdaCDM model. Using a weak prior 40 < ... More

First results from the Very Small Array -- I. Observational methodsMay 22 2002Mar 04 2003The Very Small Array (VSA) is a synthesis telescope designed to image faint structures in the cosmic microwave background on degree and sub-degree angular scales. The VSA has key differences from other CMB interferometers with the result that different ... More

The CMB power spectrum out to l=1400 measured by the VSADec 20 2002Mar 05 2003We have observed the cosmic microwave background (CMB) in three regions of sky using the Very Small Array (VSA) in an extended configuration with antennas of beamwidth 2 degrees at 34 GHz. Combined with data from previous VSA observations using a more ... More

Decoherence induced by an interacting spin environment in the transition from integrability to chaosSep 10 2007We investigate the decoherence properties of a central system composed of two spins 1/2 in contact with a spin bath. The dynamical regime of the bath ranges from a fully integrable integrable limit to complete chaoticity. We show that the dynamical regime ... More

1/f noise in the Two-Body Random EnsembleMay 07 2004We show that the spectral fluctuations of the Two-Body Random Ensemble (TBRE) exhibit 1/f noise. This result supports a recent conjecture stating that chaotic quantum systems are characterized by 1/f noise in their energy level fluctuations. After suitable ... More

Black holes and wormholes in AdS branesMay 08 2010Oct 29 2011In this work we have derived a class of geometries which describe black holes and wormholes in Randall-Sundrum-type brane models, focusing mainly on asymptotically anti-de Sitter backgrounds. We show that by continuously deforming the usual four dimensional ... More

Surface solitons in quasiperiodic nonlinear photonic latticesNov 13 2011We study discrete surface solitons in semi-infinite, one-dimensional, nonlinear (Kerr), quasiperiodic waveguide arrays of the Fibonacci and Aubry-Andr\'e types, and explore different families of localized surface modes, as a function of optical power ... More

Hydrodynamic Interactions of Self-Propelled SwimmersDec 26 2012Jan 12 2013The hydrodynamic interactions of a suspension of self-propelled particles are studied using a direct numerical simulation method which simultaneously solves for the host fluid and the swimming particles. A modified version of the "Smoothed Profile" method ... More

Perturbation theory and harmonic gauge propagation in general relativity, a particular exampleFeb 20 2015We study how the changes of coordinates between the class of harmonic coordinates affect the analitycal solutions of Einstein's equations and we apply it to an analytical approach for stationary and axisymmetric solutions of Einstein equation used by ... More

DAMIC: a novel dark matter experimentOct 24 2013DAMIC (Dark Matter in CCDs) is a novel dark matter experiment that has unique sensitivity to dark matter particles with masses below 10 GeV. Due to its low electronic readout noise (R.M.S. ~3 e-) this instrument is able to reach a detection threshold ... More

Cosmological parameter estimation and Bayesian model comparison using VSA dataDec 20 2002Feb 28 2003We constrain the basic comological parameters using the first observations by the Very Small Array (VSA) in its extended configuration, together with existing cosmic microwave background data and other cosmological observations. We estimate cosmological ... More

An approximate global solution of Einstein's equations for a finite bodyNov 02 2006We obtain an approximate global stationary and axisymmetric solution of Einstein's equations which can be considered as a simple star model: a self-gravitating perfect fluid ball with constant mass density rotating in rigid motion. Using the post-Minkowskian ... More

Superradiance at the localization-delocalization crossover in tubular chlorosomesDec 08 2015We study the effect of disorder on spectral properties of tubular chlorosomes in green sulfur bacteria Cf. aurantiacus. Employing a Frenkel-exciton Hamiltonian with diagonal and off-diagonal disorder consistent with spectral and structural studies, we ... More

On the Existence of Semi-Regular SequencesDec 25 2014Semi-regular sequences over $\mathbb{F}_2$ are sequences of homogeneous elements of the algebra $ B^{(n)}=\mathbb{F}_2[X_1,...,X_n]/(X_1^2,...,X_n^2) $, which have as few relations between them as possible. They were introduced in order to assess the ... More

Search for low-mass WIMPs in a 0.6 kg day exposure of the DAMIC experiment at SNOLABJul 25 2016Nov 10 2016We present results of a dark matter search performed with a 0.6 kg day exposure of the DAMIC experiment at the SNOLAB underground laboratory. We measure the energy spectrum of ionization events in the bulk silicon of charge-coupled devices down to a signal ... More

SLiMFast: Guaranteed Results for Data Fusion and Source ReliabilityDec 21 2015Nov 12 2016We focus on data fusion, i.e., the problem of unifying conflicting data from data sources into a single representation by estimating the source accuracies. We propose SLiMFast, a framework that expresses data fusion as a statistical learning problem over ... More

Remote Sensing Image Classification with Large Scale Gaussian ProcessesOct 02 2017Oct 03 2017Current remote sensing image classification problems have to deal with an unprecedented amount of heterogeneous and complex data sources. Upcoming missions will soon provide large data streams that will make land cover/use classification difficult. Machine ... More

First Direct-Detection Constraints on eV-Scale Hidden-Photon Dark Matter with DAMIC at SNOLABNov 09 2016Apr 11 2017We present direct detection constraints on the absorption of hidden-photon dark matter with particle masses in the range 1.2-30 eV$c^{-2}$ with the DAMIC experiment at SNOLAB. Under the assumption that the local dark matter is entirely constituted of ... More

Plasma effect in Silicon Charge Coupled Devices (CCDs)May 16 2011May 28 2011Plasma effect is observed in CCDs exposed to heavy ionizing alpha-particles with energies in the range 0.5 - 5.5 MeV. The results obtained for the size of the charge clusters reconstructed on the CCD pixels agrees with previous measurements in the high ... More

Strategies for an accurate determination of the X(3872) energy from QCD lattice simulationsOct 03 2013We develop a method to determine accurately the binding energy of the X(3872) from lattice data for the $D \bar D^*$ interaction. We show that, because of the small difference between the neutral and charged components of the X(3872), it is necessary ... More

The innermost regions of the jet in NRAO 150. Wobbling or internal rotation?Oct 22 2013NRAO 150 is a very bright millimeter to radio quasar at redshift $z$=1.52 for which ultra-high-resolution VLBI monitoring has revealed a counter-clockwise jet-position-angle wobbling at an angular speed $\sim11^{\circ}$/yr in the innermost regions of ... More

The Outburst of the Blazar S40954+658 in March-April 2011Jun 09 2014We present the results of optical (R band) photometric and polarimetric monitoring and Very Long Baseline Array (VLBA) imaging of the blazar S4 0954+658, along with Fermi and gamma;-ray data during a multi-waveband outburst in 2011 March-April. After ... More