Results for "C. Riconda"

total 118998took 0.11s
From quantum to classical modelling of radiation reaction: a focus on stochasticity effectsJul 09 2017Feb 08 2018Radiation-reaction in the interaction of ultra-relativistic electrons with a strong external electromagnetic field is investigated using a kinetic approach in the weakly quantum regime ($\chi \lesssim 1$, with $\chi$ the electron quantum parameter). Three ... More
Simple Scalings for Various Regimes of Electron Acceleration in Surface Plasma WavesJun 28 2015Different electron acceleration regimes in the evanescent field of a surface plasma wave are studied by considering the interaction of a test electron with the high-frequency electromagnetic field of a surface wave. The non-relativistic and relativistic ... More
From quantum to classical modelling of radiation reaction: a focus on the radiation spectrumFeb 08 2018Soon available multi petawatt ultra-high-intensity (UHI) lasers will allow us to probe high-amplitude electromagnetic fields interacting with either ultra-relativistic electron beams or hot plasmas in the so-called moderately quantum regime. The correct ... More
Astrophysics of magnetically collimated jets generated from laser-produced plasmasDec 12 2012The generation of astrophysically relevant jets, from magnetically collimated, laser-produced plasmas, is investigated through three-dimensional, magneto-hydrodynamic simulations. We show that for laser intensities I ~ 10^12 - 10^14 W/cm^2, a magnetic ... More
Electron Weibel Instability in Relativistic Counter-Streaming Plasmas with Flow-Aligned External Magnetic FieldsDec 12 2016The Weibel instability driven by two symmetric counter-streaming relativistic electron plasmas, also referred to as current-filamentation instability, is studied in a constant and uniform external magnetic field aligned with the plasma flows. Both the ... More
Joule-level high effiency energy transfer to sub-picosecond laser pulses by a plasma-based amplifierDec 21 2018Laser plasma amplification of sub-picosecond pulses above the Joule level is demonstrated, a major milestone for this scheme to become a solution for the next-generation of ultra-high intensity lasers. By exploring over 6 orders of magnitude the influence ... More
Radiation Pressure Driven Ion Weibel Instability and Collisionless ShocksMay 15 2017Aug 11 2017The Weibel instability from counterstreaming plasma flows is a basic process highly relevant for collisionless shock formation in astrophysics. In this Letter we investigate, via two- and three- dimensional simulations, suitable configurations for laboratory ... More
Momentum Absorption and Magnetic Field Generation by Obliquely Incident LightMar 25 2019The partial reflection of an electromagnetic (EM) wave from a medium leads to absorption of momentum in the direction perpendicular to the surface (the standard radiation pressure) {and, for oblique incidence on a partially reflecting medium}, also in ... More
Extensive study of electron acceleration by relativistic surface plasmonsFeb 15 2018The excitation of surface plasmons with ultra-intense ($I\sim 5\times 10^{19}$ W/cm$^2$), high contrast ($\sim 10^{12}$) laser pulses on periodically-modulated solid targets has been recently demonstrated to produce collimated bunches of energetic electrons ... More
Evidence of resonant surface wave excitation in the relativistic regime through measurements of proton acceleration from grating targetsOct 10 2013Nov 22 2013The interaction of laser pulses with thin grating targets, having a periodic groove at the irradiated surface, has been experimentally investigated. Ultrahigh contrast ($\sim 10^{12}$) pulses allowed to demonstrate an enhanced laser-target coupling for ... More
Decay width of light quark hybrid meson from the latticeMar 06 2006Apr 13 2006Lattice QCD with $N_f=2$ flavours of sea quark is used to explore the spectrum and decay of a $J^{PC}=1^{-+}$ spin-exotic hybrid meson. We test lattice determination of S-wave decay amplitudes at threshold using $b_1 \to \pi \omega$ where agreement with ... More
Staggered Chiral Perturbation Theory with Heavy-Light MesonsSep 08 2004We merge heavy quark effective theory with staggered chiral perturbation theory to calculate heavy-light (B, D) meson quantities. We present results at NLO for the $B(D)$ meson decay constant in the partially quenched and full QCD cases, and discuss the ... More
Transverse stability of periodic traveling waves in Kadomtsev-Petviashvili equations: A numerical studyAug 16 2011We numerically investigate transverse stability and instability of so-called cnoidal waves, i.e., periodic traveling wave solutions of the Korteweg-de Vries equation, under the time-evolution of the Kadomtsev-Petviashvili equation. In particular, we find ... More
Azimuthal decorrelation of Mueller-Navelet jets at the Tevatron and the LHCApr 25 2007Nov 05 2008We study the production of Mueller-Navelet jets at hadron colliders in the Balitsky-Fadin-Kuraev-Lipatov (BFKL) framework. We show that a measurement of the relative azimuthal angle \Delta\Phi between the jets can provide a good testing ground for corrections ... More
High-dielectric constant and wide band gap inverse silver oxide phases of the ordered ternary alloys of SiO$_{2}$, GeO$_{2}$ and SnO$_{2}$Jul 14 2006Dec 01 2006High-dielectric constant and wide band gap oxides have important technological applications. The crystalline oxide polymorphs having lattice constant compatibility to silicon are particularly desirable. One recently reported candidate is the inverse silver ... More
Single crystal growth and anisotropy of CeRuPOSep 26 2007Dec 05 2007We report on the single crystal growth of the ferromagnetic Kondo lattice system CeRuPO using a Sn flux method. Magnetic susceptibility and electrical resistivity measurements indicate strong anisotropy of this structurally layered compound. They evidence ... More
8--13 micron spectroscopy of luminous and ultraluminous infrared galaxiesMar 17 1999New moderate-resolution mid-infrared spectroscopy at 10 micron of 27 infrared galaxies is presented. The galaxies have been chosen from three 60 micron selected and one 12 micron selected complete flux-limited catalogs of galaxies; 17 of these sources ... More
Solving the mystery of IapetusApr 29 2005Jul 19 2007For a much better-founded theory, check Wing Ip, GEOPHYSICAL RESEARCH LETTERS, VOL. 33, L16203, doi:10.1029/2005GL025386, 2006 (see also http://www.agu.org/journals/gl/gl0616/2005GL025386/)
Transverse charge and magnetization densities in the nucleon's chiral peripheryOct 02 2013In the light-front description of nucleon structure the electromagnetic form factors are expressed in terms of frame-independent transverse densities of charge and magnetization. Recent work has studied the transverse densities at peripheral distances ... More
Chiral dynamics and peripheral transverse densitiesAug 07 2013In the partonic (or light-front) description of relativistic systems the electromagnetic form factors are expressed in terms of frame-independent charge and magnetization densities in transverse space. This formulation allows one to identify the chiral ... More
FIRST `Winged' and `X'-shaped Radio Source CandidatesJan 10 2007Mar 16 2008A small number of double-lobed radio galaxies (17 from our own census of the literature) show an additional pair of low surface brightness `wings', thus forming an overall `X'-shaped appearance. The origin of the wings in these radio sources is unclear. ... More
Compton X-ray and Gamma-ray Emission from Extended Radio GalaxiesApr 06 2007The extended lobes of radio galaxies are examined as sources of X-ray and gamma-ray emission via inverse Compton scattering of 3K background photons. The Compton spectra of two exemplary examples, Fornax A and Centaurus A, are estimated using available ... More
Panchromatic Views of Large-scale Extragalactic JetsDec 14 2006Highlights of recent observations of extended jets in AGN are presented. Specifically, we discuss new spectral constraints enabled by Spitzer, studies of the highest-redshift (z~4) radio/X-ray quasar jets, and a new VLBA detection of superluminal motion ... More
Series of convex functions: subdifferential, conjugate and applications to entropy minimizationJun 03 2015A formula for the sub\-differential of the sum of a series of convex functions defined on a Banach space was provided by X. Y. Zheng in 1998. In this paper, besides a slight extension to locally convex spaces of Zheng's results, we provide a formula for ... More
Torsion cohomology classes and algebraic cycles on complex projective manifoldsMar 16 2004Jan 15 2005Atiyah and Hirzebruch gave examples ofeven degree torsion classes in the singularcohomology of a smooth complex projective manifold, which arenot Poincar\'{e} dual to an algebraiccycle. We notice that the order ofthese classes are small comparedto the ... More
Modified Newtonian Mechanics from an interpolating metricJan 04 2016Jun 22 2018A few years ago Baker \cite{baker} proposed a Lema$\hat{i}$tre-Tolman metric to interpolate smoothly between the Schwarzschild metric at small scales and the Friedmann-Robertson-Walker (FRW) metric at large scales. As it stands, by implementing the Bona-Stela ... More
Elements stability: a microcosmos effect?Sep 13 2006The electronic structure of heavy elements, when described in a space-time which the metric is affected by the electromagnetic interaction, presents instabilities. These instabilities increase with the atomic number, and above a critical value, become ... More
Small-x QCD effects in forward-jet and Mueller-Navelet jet productionOct 20 2005Mar 07 2006We investigate small-x QCD effects in forward-jet production in deep inelastic scattering in the kinematic regime where the virtuality of the photon and the transverse momentum of the jet are two hard scales of about the same magnitude. We show that the ... More
The Gravitational Radiaton degrees of freedom in Hyperbolic Systems for Numerical RelativityAug 06 2002The gravitational radiation degrees of freedom of freedom are described in the framework of the 3+1 decomposition of spacetime. The relationship with eigenfields of the Kidder-Scheel-Teukolsky (KST) equations is established. This relationship is used ... More
Approximate solutions for N-body Hamiltonians with identical particles in D dimensionsJul 19 2013Nov 13 2013A method based on the envelope theory is presented to compute approximate solutions for $N$-body Hamiltonians with identical particles in $D$ dimensions ($D\ge 2$). In some favorable cases, the approximate eigenvalues can be analytically determined and ... More
Schur-finiteness in $λ$-ringsNov 05 2010Nov 17 2011We introduce the notion of a Schur-finite element in a $\lambda$-ring.
Pion and Kaon masses in Staggered Chiral Perturbation TheoryApr 21 2003Jul 07 2003We show how to compute chiral logarithms that take into account both the $\cO(a^2)$ taste-symmetry breaking of staggered fermions and the fourth-root trick that produces one taste per flavor. The calculation starts from the Lee-Sharpe Lagrangian generalized ... More
Heavy-Light Semileptonic Decays in Staggered Chiral Perturbation TheoryApr 05 2007Jun 26 2007We calculate the form factors for the semileptonic decays of heavy-light pseudoscalar mesons in partially quenched staggered chiral perturbation theory (\schpt), working to leading order in $1/m_Q$, where $m_Q$ is the heavy quark mass. We take the light ... More
Pseudoscalar Decay Constants in Staggered Chiral Perturbation TheoryJun 20 2003Sep 29 2003In a continuation of an ongoing program, we use staggered chiral perturbation theory to calculate the one-loop chiral logarithms and analytic terms in the pseudoscalar meson leptonic decay constants, $f_{\pi^+_5}$ and $f_{K^+_5}$. We consider the partially ... More
New construction of algebro-geometric solutions to the Camassa-Holm equation and their numerical evaluationSep 24 2011Dec 06 2011An independent derivation of solutions to the Camassa-Holm equation in terms of multi-dimensional theta functions is presented using an approach based on Fay's identities. Reality and smoothness conditions are studied for these solutions from the point ... More
Observations of Galaxy Clustering at High RedshiftNov 25 1998This paper reviews the current status of measurements of galaxy clustering at high redshifts (z > 0.3). The focus is on the inherent limitations in the observation and interpretation of the ``evolution of clustering''. It is likely that results from the ... More
Properties of light scalar mesons from lattice QCDApr 12 2006Jul 10 2006Lattice QCD with $N_f=2$ flavours of sea quark is used to explore the spectrum and decay of scalar mesons. We are able to determine the $b_1$ - $a_0$ mass difference and this leads to the conclusion that the lightest non-singlet scalar meson ($a_0$) has ... More
Radio-Quiet Quasars in the Direction of the Northern Hubble Deep FieldSep 13 2000We match quasars discovered in a multi-color survey centered on the northern Hubble Deep Field (HDF) with radio sources from an ultra-deep radio survey. Although 3 out of 12 quasars are detected at a level below 0.2 mJy at 1.4 GHz, all of the quasars ... More
Super-Massive Neutron StarsNov 30 2007We present here the results of Arecibo timing of PSR B1516+02B, a 7.95-ms pulsar in a binary system with a ~0.17 solar mass companion and an orbital period of 6.85 days located in the globular cluster M5. The eccentricity of the orbit (e = 0.14) has allowed ... More
A Multi-scale Subtraction Scheme and Partial Renormalization Group Equations in the $O(N)$-symmetric $φ^4$-theoryApr 23 1996To resum large logarithms in multi-scale problems a generalization of $\MS$ is introduced allowing for as many renormalization scales as there are generic scales in the problem. In the new \lq\lq minimal multi-scale subtraction scheme'' standard perturbative ... More
Bound-free $\mathbf{e}^+ \mathbf{e}^-$ pair creation with a linearly polarized laser field and a nuclear fieldJul 28 2008The process of bound-free pair production of electrons and positrons in combined laser and Coulomb fields is investigated. It is assumed that an ion collides at relativistic speed with an intense x-ray laser beam of linear polarization. The process proceeds ... More
Towards Automated Verification of Web ServicesNov 11 2011This paper proposes the use of model-checking software technology for the verification of workflows and business processes behaviour based on web services, namely the use of the SPIN model checker. Since the specification of a business process behaviour ... More
Mass Loss in 2D ZAMS Stellar ModelsMay 04 2011A large number of massive stars are known to rotate, resulting in significant distortion and variation in surface temperature from the pole to the equator. Radiatively driven mass loss is temperature dependent, so rapid rotation produces variation in ... More
Variable Modified Newtonian Mechanics from an interpolating metric II Galactic rotational curveFeb 05 2018Feb 06 2018We use an interpolating metric from a previous work \cite{wong} with a variable modified Newtonian potential (VMOND) to explore the issue of flatten rotational curve of a galaxy. We examine a model of a large protogalactic cloud with growing density perturbation, ... More
On the cusp form motives in genus 1 and level 1Apr 20 2005Jan 23 2006We prove that the moduli space of stable n-pointed curves of genus one and the projector associated to the alternating representation of the symmetric group on n letters define (for n>1) the Chow motive corresponding to cusp forms of weight n+1 for SL(2,Z). ... More
Hadronic matrix elements of neutral-meson mixing through lattice QCDSep 23 2015Neutral-meson mixing is loop suppressed in the Standard Model, leading to the possibility of enhanced sensitivity to new physics. The uncertainty in Standard Model predictions for $B$-meson oscillation frequencies is dominated by theoretical uncertainties ... More
On some results of Cufaro Petroni about Student t-processesMar 21 2008This paper deals with Student t-processes as studied in (Cufaro Petroni N 2007 J. Phys. A, Math. Theor. 40(10), 2227-2250). We prove and extend some conjectures expressed by Cufaro Petroni about the asymptotical behavior of a Student t-process and the ... More
Projective invariants of CR-hypersurfacesOct 27 2010We study the equivalence problem under projective transformation for CR-hypersurfaces of complex projective space. A complete set of projective differential invariants for analytic hypersurfaces is given. The self-dual strongly C-linearly convex hypersurfaces ... More
$K_L\toγν\barν$ in the Light Front ModelApr 17 2000We study the CP conserving and violating contributions to the decay of $\knng$ in the standard model. In our analysis, we use the form factors for $K\to\gamma$ transitions calculated directly in the entire physical range of momentum transfer within the ... More
Generating functional analysis of Minority Games with real market historiesOct 13 2004It is shown how the generating functional method of De Dominicis can be used to solve the dynamics of the original version of the minority game (MG), in which agents observe real as opposed to fake market histories. Here one again finds exact closed equations ... More
Statistical Mechanics of Recurrent Neural Networks II. DynamicsJun 01 2000A lecture notes style review of the non-equilibrium statistical mechanics of recurrent neural networks with discrete and continuous neurons (e.g. Ising, graded-response, coupled-oscillators). To be published in the Handbook of Biological Physics (North-Holland). ... More
Non-equilibrium statistical mechanics of Minority GamesMay 13 2002In this paper I give a brief introduction to a family of simple but non-trivial models designed to increase our understanding of collective processes in markets, the so-called Minority Games, and their non-equilibrium statistical mathematical analysis. ... More
NSV 13983: A New Dwarf Nova in the Period GapJun 17 2008Aims. NSV 13983 is catalogued as a dwarf nova based on a reported outburst from 2005. The system has not yet been studied spectroscopically. We attempt to confirm its nature as a dwarf nova and determine its orbital period. Methods. We derive the orbital ... More
Computation of the topological type of a real Riemann surfaceApr 21 2012We present an algorithm for the computation of the topological type of a real compact Riemann surface associated to an algebraic curve, i.e., its genus and the properties of the set of fixed points of the anti-holomorphic involution $\tau$, namely, the ... More
A new and trivial CP symmetry for extended $A_4$ flavorJan 05 2016May 18 2016The combination of $\nu_\mu$-$\nu_\tau$ exchange together with CP conjugation in the neutrino sector (known as $\mathrm{CP}^{\mu\tau}$ symmetry or $\mu\tau$-reflection) is known to predict the viable pattern: $\theta_{23}=45^\circ$, maximal Dirac CP phase ... More
Symmetric cohomology of groups as a Mackey functorDec 05 2014Symmetric cohomology of groups, defined by M. Staic in [2], is similar to the way one defines the cyclic cohomology for algebras. We show that there is a well-defined restriction, conjugation and transfer map in symmetric cohomology, which form a Mackey ... More
Scaling of the superfluid density in severely underdoped YBa2Cu3O6+yNov 20 2009Recent measurements on extremely-underdoped YBa2Cu3O6+y [Phys. Rev. Lett. 99, 237003 (2007)] have allowed the critical temperature (T_c), superfluid density [rho_0 (T << T_c)] and dc conductivity [sigma_dc (T ~ T_c)] to be determined for a series of electronic ... More
Quantum-mechanical picture of peripheral chiral dynamicsMar 06 2015The nucleon's peripheral transverse charge and magnetization densities are computed in chiral effective field theory. The densities are represented in first-quantized form, as overlap integrals of chiral light-front wave functions describing the transition ... More
Eclipsing Binary PulsarsApr 05 2004The first eclipsing binary pulsar, PSR B1957+20, was discovered in 1987. Since then, 13 other eclipsing low-mass binary pulsars have been found, 12 of these are in globular clusters. In this paper we list the known eclipsing binary pulsars and their properties, ... More
Poincare duality in dimension 3Oct 03 2004The paper gives a review of progress towards extending the Thurston programme to the Poincare duality case. For a full abstract, see the published version at the above link.
The Pulsar Population in Globular Clusters and in the GalaxyOct 15 2012Oct 23 2012In this paper, I review some of the basic properties of the pulsar population in globular clusters (GCs) and compare it with the the Galactic disk population. The neutron stars (NSs) in GCs were likely formed - and appear to continue forming - in highly ... More
Constraining The Hubble Parameter Using Distance Modulus - Redshift RelationJul 09 2015Mar 11 2016Using the relation between distance modulus $(m - M)$ and redshift $z$, deduced from Friedman- Robertson-Walker (FRW) metric and assuming different values of deceleration parameter $q_0$. We constrained the Hubble parameter $h$. The estimates of the Hubble ... More
Magnetic field dependence of the antiferromagnetic phase transitions in Co-doped YbRh_2Si_2Aug 10 2009We present first specific-heat data of the alloy Yb(Rh_(1-x)Co_x)_2Si_2 at intermediate Co-contents x=0.18, 0.27, and 0.68. The results already point to a complex magnetic phase diagram as a function of composition. Co-doping of YbRh_2Si_2 (T_N^{x=0}=72 ... More
The 8-13 Micron Spectrum of Arp 299CFeb 19 1993Arp 299C is a $5 \times 10^{10}$ \Lsun infrared source in the merging galaxy system Arp 299. It is the most luminous object known that is not obviously associated with a galaxy nucleus. Our data show that the 8--13 \mum spectrum of Arp 299C has a strong ... More
Constrained systems described by Nambu mechanicsMay 29 1996Using the framework of Nambu's generalised mechanics, we obtain a new description of constrained Hamiltonian dynamics, involving the introduction of another degree of freedom in phase space, and the necessity of defining the action integral on a world ... More
Similarity solutions of Reaction-Diffusion equation with space- and time-dependent diffusion and reaction termsAug 01 2015We consider solvability of the generalized reaction-diffusion equation with both space- and time-dependent diffusion and reaction terms by means of the similarity method. By introducing the similarity variable, the reaction-diffusion equation is reduced ... More
Center motions of nonoverlapping condensates coupled by long-range dipolar interaction in bilayer and multilayer stacksJun 11 2012We investigate the effect of anisotropic and long-range dipole-dipole interaction (DDI) on the center motions of nonoverlapping Bose-Einstein condensates (BEC) in bilayer and multilayer stacks. In the bilayer, it is shown analytically that while DDI plays ... More
A theorem of Mislin for cohomology of fusion systems and applications to block algebras of finite groupsNov 15 2013Dec 10 2014We give an algebraic proof for a theorem of Mislin in the case of cohomology of saturated fusion systems defined on p-groups when p is odd. Some applications of this theorem to block algebras of finite groups are also given.
Stückelberg Field Shiftting Quantization of Free-Particle on D-Dimensional SphereAug 11 2000In this paper we quantize the free-particle on a D-dimensional sphere in an unambiguous way by converting the second-class constraint using St\"uckelberg field shiftting formalism. Further, we argument that this formalism is equivalent to the BFFT constraint ... More
Entanglement and topological entropy of the toric code at finite temperatureApr 27 2007Nov 01 2007We calculate exactly the von Neumann and topological entropies of the toric code as a function of system size and temperature. We do so for systems with infinite energy scale separation between magnetic and electric excitations, so that the magnetic closed ... More
Dynamical shift conditions for the Z4 and BSSN hyperbolic formalismsJan 07 2004Mar 22 2004A class of dynamical shift conditions is shown to lead to a strongly hyperbolic evolution system, both in the Z4 and in the BSSN Numerical Relativity formalisms. This class generalizes the harmonic shift condition, where light speed is the only non-trivial ... More
Auger recombination and carrier multiplication in embedded silicon and germanium nanocrystalsSep 10 2007Apr 16 2008For Si and Ge nanocrystals (NCs) embedded in wide band-gap matrices, Auger recombination (AR) and carrier multiplication (CM) lifetimes are computed exactly in a three-dimensional real space grid using empirical pseudopotential wave functions. Our results ... More
Theoretical study of the insulating oxides and nitrides: SiO2, GeO2, Al2O3, Si3N4, and Ge3N4Oct 06 2006Jul 23 2007An extensive theoretical study is performed for wide bandgap crystalline oxides and nitrides, namely, SiO_{2}, GeO_{2}, Al_{2}O_{3}, Si_{3}N_{4}, and Ge_{3}N_{4}. Their important polymorphs are considered which are for SiO_{2}: $\alpha$-quartz, $\alpha$- ... More
A simple stochastic model for the evolution of protein lengthsMar 26 2007Mar 26 2007We analyse a simple discrete-time stochastic process for the theoretical modeling of the evolution of protein lengths. At every step of the process a new protein is produced as a modification of one of the proteins already existing and its length is assumed ... More
Staggered Chiral Perturbation TheoryAug 28 2003We discuss how to formulate a staggered chiral perturbation theory. This amounts to a generalization of the Lee-Sharpe Lagrangian to include more than one flavor (i.e. multiple staggered fields), which turns out to be nontrivial. One loop corrections ... More
Dark Matter in a single-metric universeJan 04 2016Mar 01 2016A few years ago Baker proposed a metric, implementing the Bona-Stela construction, which interpolates smoothly between the Schwarzschild metric at small scales and the Friedmann-Robertson-Walker (FRW) metric at large scales. As it stands, by enforcing ... More
Light-front representation of chiral dynamics in peripheral transverse densitiesMar 16 2015The nucleon's electromagnetic form factors are expressed in terms of the transverse densities of charge and magnetization at fixed light-front time. At peripheral transverse distances $b = O(M_\pi^{-1})$ the densities are governed by chiral dynamics and ... More
Eccentric Binary Millisecond PulsarsJul 18 2009In this paper we review the recent discovery of several millisecond pulsars (MSPs) in eccentric binary systems. Timing these MSPs we were able to estimate (and in one case precisely measure) their masses. These results suggest that, as a class, MSPs have ... More
Detection of Optical Synchrotron Emission from the Radio Jet of 3C279Oct 08 2002Nov 05 2002We report the detection of optical and ultraviolet emission from the kiloparsec scale jet of the well-known quasar 3C~279. A bright knot, discovered in archival V and U band {\it Hubble Space Telescope} Faint Object Camera images, is coincident with a ... More
Understanding Convolutional Neural Networks with A Mathematical ModelSep 14 2016Nov 02 2016This work attempts to address two fundamental questions about the structure of the convolutional neural networks (CNN): 1) why a non-linear activation function is essential at the filter output of every convolutional layer? 2) what is the advantage of ... More
On the density of the sum of two independent Student t-random vectorsJun 16 2009In this paper, we find an expression for the density of the sum of two independent $d-$dimensional Student $t-$random vectors $\mathbf{X}$ and $\mathbf{Y}$ with arbitrary degrees of freedom. As a byproduct we also obtain an expression for the density ... More
Quantum mechanics in curved space-timeSep 13 2004May 13 2005In this paper, the principles of the general relativity are used to formulate quantum wave equations for spin-0 and spin-1/2 particles. More specifically, the equations are worked in a Schwarzschild-like metric. As a test, the hydrogen atom spectrum is ... More
On the numerical evaluation of algebro-geometric solutions to integrable equationsJul 11 2011Dec 06 2011Physically meaningful periodic solutions to certain integrable partial differential equations are given in terms of multi-dimensional theta functions associated to real Riemann surfaces. Typical analytical problems in the numerical evaluation of these ... More
Solving the Poisson equation on small aspect ratio domains using unstructured meshesDec 10 2009We discuss the ill conditioning of the matrix for the discretised Poisson equation in the small aspect ratio limit, and motivate this problem in the context of nonhydrostatic ocean modelling. Efficient iterative solvers for the Poisson equation in small ... More
Transverse-Longitudinal Coupling by Space Charge in CyclotronsSep 09 2011Jan 04 2012A method is presented that enables to compute the parameters of matched beams with space charge in cyclotrons with emphasis on the effect of the transverse-longitudinal coupling. Equations describing the transverse-longitudinal coupling and corresponding ... More
Comparison of photometric variability before and after stellar flaresDec 02 2013The energy in the solar acoustic spectrum is known to be correlated with flares, but it is not known if the same is true for stellar flares? In order to answer this question, we have analyzed 73 flares in 39 solar-like stars. These flares were identified ... More
Nucleon-Nucleon Correlations in Electromagnetically Induced Knockout ReactionsNov 28 2001The attempts to investigate correlations in electromagnetically induced one- and two-nucleon knockout are reviewed. The theoretical framework for cross section calculations is outlined and some results are presented for the exclusive $^{16}$O($e,e'p)^{15}$N ... More
Graphical analysis of Current-Voltage Characteristics in Typical Memristive InterfacesSep 14 2016Nov 07 2016A graphical representation based on the isothermal current-voltage (IV) measurements of typical memristive interfaces is presented. This is the starting point to extract relevant microscopic information of the parameters that control the electrical properties ... More
Jackson's q-exponential as the exponential of a seriesMay 02 2003Jackson's q-exponential is expressed as the exponential of a series whose coefficients are obtained in closed form. Such a relation is used to derive some properties of the q-exponential.
Coloured Hopf algebras and their dualsNov 14 1997Coloured Hopf algebras, related to the coloured Yang-Baxter equation, are reviewed, as well as their duals. The special case of coloured quantum universal enveloping algebras provides a coloured extension of Drinfeld and Jimbo formalism. The universal ... More
Cryogenic safety aspect of the low -βmagnet systems at the Large Hadron Collider (LHC)Aug 08 2012The low -\beta magnet systems are located in the LHC insertion regions around the four interaction points. They are the key elements in the beams focusing/defocusing process and will allow proton collisions at a luminosity of up to 10**34/cm**2s. Large ... More
Theoretical Approaches to HERA PhysicsJan 11 2002A review is presented of the different theoretical models proposed to approach consistently the interplay between soft and hard physics, that can now be studied experimentally at HERA for the first time.
Galactic Positrons as a Probe of Large Extra DimensionsDec 24 2008Dec 24 2008In the last decade, there has been increased interest in the possibility that the Universe contains large additional dimensions. In this article it is proposed that the Kaluza-Klein modes which are predicted to exist in such models will be trapped in ... More
Polarization analysis of K-edge resonant x-ray scattering of germaniumOct 10 2002May 01 2003The polarization of K-edge resonant scattering at the space group ``forbidden'' (0 0 6) reflection of Ge was measured as function of the azimuthal angle, psi. The experimental results are compared to model calculations based on symmetry analysis of the ... More
The structure of the proton and NLO QCD fitsNov 25 2005HERA has provided a wealth of high precision structure function and jet production data, allowing considerable progress to be made in understanding the structure of the proton. In this paper, several of the most recent proton structure results from the ... More
ExoticsFeb 04 2003We review lattice QCD results for glueballs (including a discussion of mixing with scalar mesons), hybrid mesons and other exotic states (such as $B_s B_s$ molecules).
Hadronic Physics from the LatticeSep 27 1995Sep 28 1995We present the lattice gauge theory approach to evaluating non-perturbative hadronic interactions from first principles. We discuss applications to glueballs, inter-quark potentials, the running coupling constant, the light hadron spectrum and the pseudoscalar ... More
Staggered Chiral Perturbation Theory for Neutral B MixingNov 01 2012I describe a calculation of B meson mixing at one-loop in staggered chiral perturbation theory, for the complete set of Standard Model and beyond-the-Standard Model operators. The particular lattice representation of the continuum operators used by the ... More
Harrison transformation of hyperelliptic solutions and charged dust disksDec 22 2005We use a Harrison transformation on solutions to the stationary axisymmetric Einstein equations to generate solutions of the Einstein-Maxwell equations. The case of hyperelliptic solutions to the Ernst equation is studied in detail. Analytic expressions ... More