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One new variable candidate and six nonvariable stars at the ZZ Ceti instability stripFeb 08 2019We present our results on the continuation of our survey searching for new ZZ Ceti stars, inspired by the recently launched TESS space mission. The seven targets were bright DA-type white dwarfs located close to the empirical ZZ Ceti instability strip. ... More

Searching for new white dwarf pulsators for TESS observations at Konkoly ObservatoryMay 25 2018We present the results of our survey searching for new white dwarf pulsators for observations by the TESS space telescope. We collected photometric time-series data on 14 white dwarf variable-candidates at Konkoly Observatory, and found two new bright ... More

The weakening outburst of the young eruptive star V582 AurFeb 10 2019V582 Aur is a pre-main sequence FU Orionis type eruptive star, which entered a brightness minimum in 2016 March due to changes in the line-of-sight extinction. Here, we present and analyze new optical $B$, $V$, $R_C$ and $I_C$ band multiepoch observations ... More

Wandering near the red edge: photometric observations of three cool ZZ Ceti starsOct 23 2018We summarize our findings on three cool ZZ Ceti type pulsating white dwarfs. We determined eight independent modes in HS 0733+4119, of which seven are new findings. For GD 154, we detected two new eigenmodes, and the recurrence of the pulsational behaviour ... More

Photometric and Spectroscopic Properties of Type Ia Supernova 2018oh with Early Excess Emission from the $Kepler$ 2 ObservationsNov 25 2018Supernova (SN) 2018oh (ASASSN-18bt) is the first spectroscopically-confirmed type Ia supernova (SN Ia) observed in the $Kepler$ field. The $Kepler$ data revealed an excess emission in its early light curve, allowing to place interesting constraints on ... More

The First Post-Kepler Brightness Dips of KIC 8462852Jan 02 2018We present a photometric detection of the first brightness dips of the unique variable star KIC 8462852 since the end of the Kepler space mission in 2013 May. Our regular photometric surveillance started in October 2015, and a sequence of dipping began ... More

Understanding Convolutional Neural Networks with A Mathematical ModelSep 14 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

Threshold effects in open-string theoryMay 05 1996May 14 1996We analyze the one-loop effective gauge-field action in $Z_2$-orbifold compactifications of type-I theory. We show how, for non-abelian group factors, the threshold effects are ultraviolet finite though given entirely by a six-dimensional field theory ... More

Hidden Symmetry of a Fluid Dynamical ModelMay 28 2001A connection between solutions of the relativistic d-brane system in (d+1) dimensions with the solutions of a Galileo invariant fluid in d-dimensions is by now well established. However, the physical nature of the light-cone gauge description of a relativistic ... More

A quantum topological phase transition at the microscopic levelJul 13 2007Mar 01 2008We study a quantum phase transition between a phase which is topologically ordered and one which is not. We focus on a spin model, an extension of the toric code, for which we obtain the exact ground state for all values of the coupling constant that ... More

Explicit Gravitational Radiation in Hyperbolic Systems for Numerical RelativityFeb 14 2002Feb 28 2002A method for studying the causal structure of space-time evolution systems is presented. This method, based on a generalization of the well known Riemann problem, provides intrinsic results which can be interpreted from the geometrical point of view. ... More

Flux Limiter Methods in 3D Numerical RelativityFeb 28 2002New numerical methods have been applied in relativity to obtain a numerical evolution of Einstein equations much more robust and stable. Starting from 3+1 formalism and with the evolution equations written as a FOFCH (first-order flux conservative hyperbolic) ... More

Staggered Chiral Perturbation Theory for Heavy-Light MesonsOct 18 2005Jan 25 2006We incorporate heavy-light mesons into staggered chiral perturbation theory, working to leading order in 1/m_Q, where m_Q is the heavy quark mass. At first non-trivial order in the chiral expansion, staggered taste violations affect the chiral logarithms ... More

Replica methods for loopy sparse random graphsJan 29 2016I report on the development of a novel statistical mechanical formalism for the analysis of random graphs with many short loops, and processes on such graphs. The graphs are defined via maximum entropy ensembles, in which both the degrees (via hard constraints) ... More

Statistical Mechanics of Recurrent Neural Networks I. StaticsJun 01 2000A lecture notes style review of the equilibrium statistical mechanics of recurrent neural networks with discrete and continuous neurons (e.g. Ising, coupled-oscillators). To be published in the Handbook of Biological Physics (North-Holland). Accompanied ... More

Observational constraints upon quintessence models arising from moduli fieldsApr 14 2000Jun 12 2000We study observational constraints on cosmological models with a quintessence arising from moduli fields. The scalar field potential is given by a double exponential potential V=V_0 exp(-A e^{sqrt{2} kappa phi}). After reviewing the properties of the ... More

Light-front representation of chiral dynamics with Delta isobar and large-N_c relationsMar 29 2016Transverse densities describe the spatial distribution of electromagnetic current in the nucleon at fixed light-front time. At peripheral distances b = O(M_pi^{-1}) the densities are governed by chiral dynamics and can be calculated model-independently ... More

Radio Identification of the X-ray Jet in the z=4.3 Quasar GB 1508+5714Oct 25 2003Dec 01 2003The recent discovery of an X-ray jet in the z=4.3 quasar GB 1508+5714 by Yuan et al. (astro-ph/0309318) and Siemiginowska et al. (astro-ph/0310241) prompted a search for its radio counterpart. Here, we report the successful discovery of faint radio emission ... More

CNN as Guided Multi-layer RECOS TransformJan 30 2017Feb 19 2017There is a resurging interest in developing a neural-network-based solution to the supervised machine learning problem. The convolutional neural network (CNN) will be studied in this note. To begin with, we introduce a RECOS transform as a basic building ... More

The classical overdetermined Serrin problemNov 29 2017Nov 30 2017In this survey we consider the classical overdetermined problem which was studied by Serrin in 1971. The original proof relies on Alexandrov's moving plane method, maximum principles, and a refinement of Hopf's boundary point Lemma. Since then other approaches ... More

Multi-scale RenormalizationDec 18 1996The Standard MS renormalization prescription is inadequate for dealing with multi-scale problems. To illustrate this we consider the computation of the effective potential in the Higgs-Yukawa model. It is argued that it is natural to employ a two-scale ... More

Electroweak standard model at finite temperature in presence of a bosonic chemical potentialMar 15 2007Dec 30 2010We study the electroweak standard model at finite temperature in presence of a bosonic chemical potential associated with the conserved electromagnetic current. To preserve the thermodynamic equilibrium of the system, the thermal medium is neutralized ... More

Basic Morita equivalences and a conjecture of Sasaki for cohomology of block algebras of finite groupsJun 14 2015We show, using basic Morita equivalences between block algebras of finite groups, that the Conjecture of H. Sasaki from [9] is true for a new class of blocks called nilpotent covered blocks. When this Conjecture is true we define some transfer maps between ... More

K2 Observations of SN 2018oh Reveal a Two-Component Rising Light Curve for a Type Ia SupernovaNov 25 2018We present an exquisite, 30-min cadence Kepler (K2) light curve of the Type Ia supernova (SN Ia) 2018oh (ASASSN-18bt), starting weeks before explosion, covering the moment of explosion and the subsequent rise, and continuing past peak brightness. These ... 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

Reply to cond-mat/0503325: Comment on `Generating functional analysis of Minority Games with real merket histories' by KH Ho, WC Man, FK Chow and HF ChauMar 21 2005The Comment cond-mat/0503325 is built around two core statements, both of which are plainly incorrect.

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

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

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

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

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

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

Magnetic Charge in a Nonassociative Field TheoryMay 01 1996The violation of the Jacobi identity by the presence of magnetic charge is accomodated by using an explicitly nonassociative theory of octonionic fields. It is found that the dynamics of this theory is simplified if the Lagrangian contains only dyonic ... More

Using modified Gaussian distribution to study the physical properties of one and two-component ultracold atomsDec 20 2006Gaussian distribution is commonly used as a good approximation to study the trapped one-component Bose-condensed atoms with relatively small nonlinear effect. It is not adequate in dealing with the one-component system of large nonlinear effect, nor the ... More

Oscillations of Bose condensates in a one-dimensional optical superlatticeDec 30 2005Oscillations of atomic Bose-Einstein condensates in a 1D optical lattice with a two-point basis is investigated. In the low-frequency regime, four branches of modes are resolved, that correspond to the transverse in-phase and out-of-phase breathing modes, ... 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

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

Chemical Equilibration of AntihyperonsFeb 15 2002Feb 25 2002Rapid chemical equilibration of antihyperons by means of the interplay between strong annihilation on baryons and the corresponding backreactions of multi-mesonic (fusion-type) processes in the later, hadronic stage of an ultrarelativistic heavy ion collision ... More

Nuclear Corrections in Neutrino Deep Inelastic Scattering and the Extraction of the Strange Quark DistributionJun 18 1998Jun 23 1998Recent measurement of the structure function $F_2^\nu$ in neutrino deep inelastic scattering allows us to compare structure function measured in neutrino and charged lepton scattering for the first time with reasonable precision. The comparison between ... More

Light-Cone Meson-Baryon Fluctuations and Single-Spin AsymmetriesJun 15 1998Feb 09 1999We show that energetically favored meson-baryon fluctuations present in the light-cone wave function of a transversely polarized proton can account for the left-right asymmetries measured in inclusive meson production processes.

Inclusive production of charged pions in p+p collisions at 158 GeV/c beam momentumOct 04 2005New results on the production of charged pions in p+p interactions are presented. The data come from a sample of 4.8 million inelastic events obtained with the NA49 detector at the CERN SPS at 158 GeV/c beam momentum. Pions are identified by energy loss ... More

Models of Non-Minimal Chaotic Inflation in SupergravityJul 30 2013Dec 11 2014We show how we can implement chaotic inflation in the context of supergravity by conveniently selecting the functional form of a strong enough non-minimal coupling between the inflaton and the Ricci scalar curvature. The procedure can be applied when ... More

Kination Dominated Reheating and Cold Dark Matter AbundanceOct 18 2005Oct 31 2006We consider the decay of a massive particle under the complete or partial domination of the kinetic energy density generated by a quintessential exponential model and we impose a number of observational constraints originating from nucleosynthesis, the ... More

Kinetically Modified Non-Minimal Chaotic InflationMar 19 2015Aug 31 2015We consider Supersymmetric (SUSY) and non-SUSY models of chaotic inflation based on the phi^n potential with 2<=n<=6. We show that the coexistence of a nonminimal coupling to gravity, fR=1+cR phi^(n/2), with a kinetic mixing of the form fK=cK fR^m can ... More

Comparing proteins by their internal dynamics: exploring structure-function relationships beyond static structural alignmentsDec 17 2012The growing interest for comparing protein internal dynamics owes much to the realization that protein function can be accompanied or assisted by structural fluctuations and conformational changes. Analogously to the case of functional structural elements, ... More

Multiplicative structures on algebraic K-theoryApr 17 2013Jul 16 2014Algebraic K-theory is the stable homotopy theory of homotopy theories, and it interacts with algebraic structures accordingly. In particular, we prove the Deligne Conjecture for algebraic K-theory.

Topological rigidification of schemesDec 08 2010We show that any of a large class of schemes receives a universal homeomorphism from a reduced scheme that in turn receives no nontrivial universal homeomorphism from any other reduced scheme. This construction serves as a categorical input for the formal ... More

Statistical Mechanics of Entropy Production: Gibbsian hypothesis and local fluctuationsJun 22 2001Jul 09 2001It is argued that a Gibbsian formula for the space-time distribution of microscopic trajectories of a nonequilibrium system provides a unifying framework for recent results on the fluctuations of the entropy production. The variable entropy production ... More

SAMPIC: a readout chip for fast timing detectors in particle physics and medical imagingMar 16 2015We describe the new fast timing readout chip SAMPIC developed in CEA Saclay and in LAL Orsay (France) as well as the results of differents tests performed using that chip.

On the Factorisation of the Connected Prescription for Yang-Mills AmplitudesDec 22 2006We examine factorisation in the connected prescription of Yang-Mills amplitudes. The multi-particle pole is interpreted as coming from representing delta functions as meromorphic functions. However, a naive evaluation does not give a correct result. We ... More

What is the Usefulness of Frequentist Confidence Intervals?Mar 01 2000The following questions are discussed: ``Why confidence intervals are a hot topic?''; ``Are confidence intervals objective?''; ``What is the usefulness of coverage?''; ``How to obtain useful information from experiment?''; ``The confidence level must ... More

A new ordering principle for the classical statistical analysis of Poisson processes with backgroundAug 06 1998May 06 1999Inspired by the recent proposal by Feldman and Cousins of a ``unified approach to the classical statistical analysis of small signals'' based on a choice of ordering in Neyman's construction of classical confidence intervals, I propose a new ordering ... More

Status of Neutrino FitsMay 13 2003I review the current status of solar, KamLAND, atmospheric and K2K neutrino experiments, implications for three-neutrino mixing and upper bounds for the neutrino masses.

Last CPT-Invariant Hope for LSND Neutrino OscillationsFeb 19 2003Feb 21 2003It is shown that the 99% confidence limits from the analyses of the data of cosmological and neutrino experiments imply a small marginally allowed region in the space of the neutrino oscillation parameters of 3+1 four-neutrino mixing schemes. This region ... More

Enhancing the physical significance of Frequentist confidence intervalsFeb 15 2000It is shown that all the Frequentist methods are equivalent from a statistical point of view, but the physical significance of the confidence intervals depends on the method. The Bayesian Ordering method is presented and confronted with the Unified Approach ... More

Zeeman response of d-wave superconductors: Born approximation for impurity and spin-orbit scattering potentialsJul 01 1999The effects of impurity and spin-orbit scattering potentials can strongly affect the Zeeman response of a d-wave superconductor. Here, both the phase diagram and the quasiparticle density of states are calculated within the Born approximation and it is ... More

Electron Spin Dynamics in Impure Quantum Wells for Arbitrary Spin-Orbit CouplingJan 09 2005Mar 28 2005Strong interest has arisen recently on low-dimensional systems with strong spin-orbit interaction due to their peculiar properties of interest for some spintronic applications. Here, the time evolution of the electron spin polarization of a disordered ... More

How and when can one identify hadronic molecules in the baryon spectrumNov 05 2007A method to identify hadronic molecules in the particle spectrum is reviewed and the conditions for its applicability discussed. Special emphasis is put on the discussion of molecule candidates in the baryon spectrum.

Meson production in nucleon--nucleon collisions close to the thresholdNov 26 2003Mar 24 2004The last decade has witnessed great experimental progress that has led to measurements of cross sections--polarized as well as unpolarized--of of high accuracy in several $NN \to NNx$ reaction channels. These data, naturally, pose challenges to theorists ... More

Pion reactions on two--nucleon systemsMar 12 2007We review recent progress in our understanding of elastic and inelastic pion reactions on two nucleon systems from the point of view of effective field theory. The discussion includes pion-deuteron scattering, gamma d to pi-nn, and NN to NNpi. At the ... More

Diagrammatic Derivation of Lovelock DensitiesFeb 16 2009Apr 19 2009We discuss a method of calculating the various scalar densities encountered in Lovelock theory which relies on diagrammatic, instead of algebraic manipulations. Taking advantage of the known symmetric and antisymmetric properties of the Riemann tensor ... More

Photoproduction of K^0 and Lambda at HERA and a Comparison with Deep Inelastic ScatteringMay 28 1997May 29 1997Inclusive $K^0$ and $\Lambda$ photoproduction has been investigated at HERA with the H1 detector at an average photon-proton center of mass energy of 200 GeV in the transverse momentum range 0.5 <p_t <5 GeV. The production rates as a function of $p_t$ ... More

Charmonium Production in Deep Inelastic Scattering at HERAMar 09 1999The electroproduction of J/psi and psi(2S) mesons is studied in elastic, quasi-elastic and inclusive reactions for four momentum transfers 2 < Q^2 < 80 GeV^2 and photon-proton centre of mass energies 25 < W < 180 GeV. The data were taken with the H1 detector ... More

Measurement of Internal Jet Structure in Dijet Production in Deep-Inelastic Scattering at HERAJan 09 1999Internal jet structure in dijet production in deep-inelastic scattering is measured with the H1 detector at HERA. Jets with transverse energies ET,Breit > 5 GeV are selected in the Breit frame employing k_perp and cone jet algorithms. In the kinematic ... More

Measurement of Dijet Cross-Sections at Low Q^2 and the Extraction of an Effective Parton Density for the Virtual PhotonDec 18 1998The triple-differential dijet cross-section, d^3 sigma_{ep}/dQ2 dE_t2 dxgjets, is measured with the H1 detector at HERA as a function of the photon virtuality Q^2, the fraction of the photon's momentum carried by the parton entering the hard scattering, ... More

Measurement of the Inclusive Di-Jet Cross Section in Photoproduction and Determination of an Effective Parton Distribution in the PhotonSep 05 1997The double-differential inclusive di-jet cross section in photoproduction processes is measured with the H1 detector at HERA. The cross section is determined as a function of the average transverse jet energy E_T^jets for ranges of the fractional energy ... More

GRBs as ultra-high energy cosmic ray sources: clues from FermiMar 27 2010If gamma-ray bursts are sources of ultra-high energy cosmic rays, then radiative signatures of hadronic acceleration are expected in GRB data. Observations with the Fermi Gamma-ray Space Telescope offer the best means to search for evidence of UHECRs ... More

High-Energy Cosmic Rays and Neutrinos from Gamma-Ray BurstsJun 16 2005A complete model for the origin of high-energy >~10^{14} eV) cosmic rays from gamma-ray bursts (GRBs) and implications of this hypothesis are described. Detection of high-energy neutrinos from GRBs provide an unambiguous test of the model. Evidence for ... More

Soft Gluon Effects on Electroweak Boson Production in Hadron CollisionsJun 17 1999Shortened table of contents: 1. Introduction 1.1 The Standard Model of Elementary Particles 1.2 The Quantum Nature of Gauge Fields 2. Soft Gluon Resummation 2.1 Lepton Pair Production at Fixed Order in $\alpha _s$ 2.2 The Resummation Formalism 3. Vector ... More

The baryonic self similarity of dark matterMay 24 2013Jun 16 2014The cosmological simulations indicates that the dark matter haloes have specific self similar properties. However the halo similarity is affected by the baryonic feedback, the momentum injected by the supernovae re-shape the dark matter core and transform ... More

Dark matter halo's and self similarityJun 28 2012Oct 29 2012This papers explores the self similar solutions of the Vlasov-Poisson system and their relation to the gravitational collapse of dynamically cold systems. Analytic solutions are derived for power law potential in one dimension, and extensions of these ... More

Perturbative reconstruction of a gravitational lens: when mass does not follow lightJan 04 2009Sep 07 2009The structure and potential of a complex gravitational lens is reconstructed using the perturbative method presented in Alard 2007, MNRAS, 382L, 58; Alard 2008, MNRAS, 388, 375. This lens is composed of 6 galaxies belonging to a small group. The lens ... More

Gravitational arcs as a perturbation of the perfect ringJun 02 2007The image of a point situated at the center of a circularly symmetric potential is a perfect circle. The perturbative effect of non-symmetrical potential terms is to displace and break the perfect circle. These 2 effects, displacement and breaking are ... More

Image subtraction with non-constant kernel solutionsMar 08 1999It is demonstrated that non-constant kernel solution, that can fit the spatial variations of the kernel can be obtained with minimum computing time. The CPU cost required with this new extension of the image subtraction method is almost the same as for ... More

MEPSA: a flexible peak search algorithm designed for uniformly spaced time seriesJan 06 2015We present a novel algorithm aimed at identifying peaks within a uniformly sampled time series affected by uncorrelated Gaussian noise. The algorithm, called "MEPSA" (multiple excess peak search algorithm), essentially scans the time series at different ... More

"Soft" PhenomenologyOct 17 1997A review of the soft supersymmetry-breaking parameters and the $\mu$ term arising in superstring models is performed paying special attention to their phenomenological implications. In particular, the violation of the scalar mass universality which may ... More

Theoretical Predictions for the Direct Detection of Supersymmetric Dark MatterDec 23 2003We compute the neutralino-nucleon cross section in several supersymmetric scenarios, taking into account all kind of experimental and astrophysical constraints. In addition, the constraints that the absence of dangerous charge and colour breaking minima ... More

Soft Terms from Dilaton/Moduli sectorsSep 13 1995We study the structure of the soft SUSY-breaking terms obtained from large classes of 4-D Strings under the assumption of dilaton/moduli dominance in the process of SUSY-breaking. In particular, we first analyze in detail the dilaton-dominated limit because ... More

Soft Supersymmetry-breaking terms and the μproblemJul 20 1995The connection between Supergravity and the low-energy world is analyzed. In particular, the soft Supersymmetry-breaking terms arising in Supergravity, the $\mu$ problem and various solutions proposed to solve it are reviewed. The soft terms arising in ... More

Galactic Black HOle Binary SystemsDec 18 2000I review observations of the X-ray spectra of Galactic Black Hole Candidates, and theoretical ideas as to how these can be produced. X-ray reflection should enable different source geometries to be distinguished, but the ionisation instability of X-ray ... More

Stability of strange quark matter in the MIT bag model and in the Color Dielectric ModelOct 09 2001We utilize the MIT bag model and two different versions of the Color Dielectric Model in order to study the properties of strange matter, and to discuss the stability of strangelets. We also investigate the effect of the introduction of perturbative gluons. ... More

Degenerations of Hodge structureJul 04 2016Two interesting questions in algebraic geometry are: (i) how can a smooth projective varieties degenerate? and (ii) given two such degenerations, when can we say that one is "more singular/degenerate" than the other? Schmid's Nilpotent Orbit Theorem yields ... More

Nilpotent cones and adjoint orbitsMay 13 2014May 27 2014A short note to show that the elements of the (open) cone underlying a nilpotent orbit on a period domain are pairwise congruent under the symmetry group of the period domain.