Results for "S. Giaccari"

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Worldline quantization of field theory, effective actions and $L_\infty$ structureFeb 08 2018We formulate the worldline quantization of a massive fermion model coupled to external higher spin sources. We use the relations obtained in this way to show that its regularized effective action is endowed with an $L_\infty$ symmetry. The same result ... More
Weyl transformations and trace anomalies in N=1, D=4 supergravitiesMay 30 2013Jul 07 2013We identify the supersymmetric extension of Weyl transformations in various types of supergravities, the minimal, nonminimal and new minimal N=1 SUGRA in 4D, formulated in terms of superfields. Based also on previous results we conclude that there are ... More
Analytic solutions for Dp branes in SFTJun 20 2011This is the follow-up of a previous paper [ArXiv:1105.5926], where we calculated the energy of an analytic lump solution in SFT, representing a D24-brane. Here we describe an analytic solution for a Dp-brane, for any p, and compute its energy.
Lump solutions in SFT. ComplementsSep 20 2011May 18 2012Recently a possible violation of the equation of motion for the recently proposed lump solutions in open SFT has been pointed out in the literature. In this paper we argue that, when the issue is considered in the appropriate mathematical setting of distribution ... More
The energy of the analytic lump solution in SFTMay 30 2011Aug 01 2013In a previous paper a method was proposed to find exact analytic solutions of open string field theory describing lower dimensional lumps, by incorporating in string field theory an exact renormalization group flow generated by a relevant operator in ... More
One-loop effective actions and higher spinsSep 07 2016Sep 15 2016The idea we advocate in this paper is that the one-loop effective action of a free (massive) field theory coupled to external sources (via conserved currents) contains complete information about the classical dynamics of such sources. We show many explicit ... More
One-loop effective actions and higher spinsSep 07 2016Nov 14 2016The idea we advocate in this paper is that the one-loop effective action of a free (massive) field theory coupled to external sources (via conserved currents) contains complete information about the classical dynamics of such sources. We show many explicit ... More
Axial gravity, massless fermions and trace anomaliesMar 30 2017May 24 2017This article deals with two main topics. One is odd parity trace anomalies in Weyl fermion theories in a 4d curved background, the second is the introduction of axial gravity. The motivation for reconsidering the former is to clarify the theoretical background ... More
Generalized states in SFTApr 08 2013Oct 18 2013The search for analytic solutions in open string fields theory \`a la Witten often meets with singular expressions, which need an adequate mathematical formalism to be interpreted. In this paper we discuss this problem and propose a way to resolve the ... More
Classical and Quantum Nonlocal SupergravityMay 12 2016We derive the N=1 supersymmetric extension for a class of weakly nonlocal four dimensional gravitational theories.The construction is explicitly done in the superspace and the tree-level perturbative unitarity is explicitly proved both in the superfield ... More
Dark Solitons, D-branes and Noncommutative Tachyon Field TheoryAug 25 2016In this paper we discuss the boson/vortex duality by mapping the Gross-Pitaevskii theory into an effective string theory, both with and without boundaries. Through the effective string theory, we find the Seiberg-Witten map between the commutative and ... More
Consistent gravitational anomalies for chiral bosonsDec 15 2008Feb 12 2009Exact consistent gravitational anomalies for chiral bosons in two dimensions are treated both with the Schwinger-DeWitt regularization and independently through a cohomological procedure. The diffeomorphism transformations are described by a single ghost ... More
Search for anisotropies in cosmic-ray positrons detected by the PAMELA experimentSep 21 2015Oct 08 2015The PAMELA detector was launched on board of the Russian Resurs-DK1 satellite on June 15, 2006. Data collected during the first four years have been used to search for large-scale anisotropies in the arrival directions of cosmic-ray positrons. The PAMELA ... More
Scattering amplitudes in super-renormalizable gravityJun 15 2015We explicitly compute the tree-level on-shell four-graviton amplitudes in four, five and six dimensions for local and weakly nonlocal gravitational theories that are quadratic in both, the Ricci and scalar curvature with form factors of the d'Alembertian ... More
Trace anomalies in chiral theories revisitedMar 11 2014Aug 29 2014Motivated by the search for possible CP violating terms in the trace of the energy-momentum tensor in theories coupled to gravity we revisit the problem of trace anomalies in chiral theories. We recalculate the latter and ascertain that in the trace of ... More
Finite Entanglement Entropy of Black HolesDec 19 2015We compute the area term contribution to the black holes' entanglement entropy for a class of local or weakly nonlocal renormalizable gravitational theories coupled to matter. For the case of super-renormalizable theories, we can get a finite conical ... More
Multi-Objective Genetic Algorithm Optimisation for an Array of Cherenkov TelescopesAug 28 2017We have conceived and implemented a multi-objective genetic algorithm (GA) code for the optimisation of an array of Imaging Atmospheric Cherenkov Telescopes (IACTs). The algorithm takes as input a series of cost functions (metrics) each describing a different ... More
MARTA: A high-energy cosmic-ray detector concept with high-accuracy muon measurementDec 20 2017Apr 20 2018A new concept for the direct measurement of muons in air showers is presented. The concept is based on resistive plate chambers (RPCs), which can directly measure muons with very good space and time resolution. The muon detector is shielded by placing ... More
MARTA: A high-energy cosmic-ray detector concept with high-accuracy muon measurementDec 20 2017A new concept for the direct measurement of muons in air showers is presented. The concept is based on resistive plate chambers (RPCs), which can directly measure muons with very good space and time resolution. The muon detector is shielded by placing ... More
Evidence for a mixed mass composition at the `ankle' in the cosmic-ray spectrumSep 27 2016Nov 22 2016We report a first measurement for ultra-high energy cosmic rays of the correlation between the depth of shower maximum and the signal in the water Cherenkov stations of air-showers registered simultaneously by the fluorescence and the surface detectors ... More
Measurement of the average shape of longitudinal profiles of cosmic-ray air showers at the Pierre Auger ObservatoryNov 12 2018The profile of the longitudinal development of showers produced by ultra-high energy cosmic rays carries information related to the interaction properties of the primary particles with atmospheric nuclei. In this work, we present the first measurement ... More
Data-driven estimation of the invisible energy of cosmic ray showers with the Pierre Auger ObservatoryJan 23 2019Feb 04 2019The determination of the primary energy of extensive air showers using the fluorescence detection technique requires an estimation of the energy carried away by particles that do not deposit all their energy in the atmosphere. This estimation is typically ... More
Search for signatures of magnetically-induced alignment in the arrival directions measured by the Pierre Auger ObservatoryNov 10 2011We present the results of an analysis of data recorded at the Pierre Auger Observatory in which we search for groups of directionally-aligned events (or `multiplets') which exhibit a correlation between arrival direction and the inverse of the energy. ... More
Calibration and Monitoring of the Pierre Auger ObservatoryJun 12 2009Reports on the atmospheric monitoring, calibration, and other operating systems of the Pierre Auger Observatory. Contributions to the 31st International Cosmic Ray Conference, Lodz, Poland, July 2009.
Upper limit on the cosmic-ray photon fraction at EeV energies from the Pierre Auger ObservatoryMar 05 2009Apr 20 2009From direct observations of the longitudinal development of ultra-high energy air showers performed with the Pierre Auger Observatory, upper limits of 3.8%, 2.4%, 3.5% and 11.7% (at 95% c.l.) are obtained on the fraction of cosmic-ray photons above 2, ... More
Studies of Cosmic Ray Composition and Air Shower Structure with the Pierre Auger ObservatoryJun 11 2009Studies of the composition of the highest energy cosmic rays with the Pierre Auger Observatory, including examination of hadronic physics effects on the structure of extensive air showers. Submissions to the 31st ICRC, Lodz, Poland (July 2009).
Reconstruction of inclined air showers detected with the Pierre Auger ObservatoryJul 11 2014We describe the method devised to reconstruct inclined cosmic-ray air showers with zenith angles greater than $60^\circ$ detected with the surface array of the Pierre Auger Observatory. The measured signals at the ground level are fitted to muon density ... More
A Targeted Search for Point Sources of EeV NeutronsJun 16 2014A flux of neutrons from an astrophysical source in the Galaxy can be detected in the Pierre Auger Observatory as an excess of cosmic-ray air showers arriving from the direction of the source. To avoid the statistical penalty for making many trials, classes ... More
Search for First Harmonic Modulation in the Right Ascension Distribution of Cosmic Rays Detected at the Pierre Auger ObservatoryMar 14 2011We present the results of searches for dipolar-type anisotropies in different energy ranges above $2.5\times 10^{17}$ eV with the surface detector array of the Pierre Auger Observatory, reporting on both the phase and the amplitude measurements of the ... More
Advanced functionality for radio analysis in the Offline software framework of the Pierre Auger ObservatoryJan 24 2011Feb 03 2011The advent of the Auger Engineering Radio Array (AERA) necessitates the development of a powerful framework for the analysis of radio measurements of cosmic ray air showers. As AERA performs "radio-hybrid" measurements of air shower radio emission in ... More
Update on the correlation of the highest energy cosmic rays with nearby extragalactic matterSep 09 2010Sep 29 2010Data collected by the Pierre Auger Observatory through 31 August 2007 showed evidence for anisotropy in the arrival directions of cosmic rays above the Greisen-Zatsepin-Kuz'min energy threshold, \nobreak{$6\times 10^{19}$eV}. The anisotropy was measured ... More
The Pierre Auger Observatory Upgrade - Preliminary Design ReportApr 13 2016The Pierre Auger Observatory has begun a major Upgrade of its already impressive capabilities, with an emphasis on improved mass composition determination using the surface detectors of the Observatory. Known as AugerPrime, the upgrade will include new ... More
Prototype muon detectors for the AMIGA component of the Pierre Auger ObservatoryMay 05 2016May 12 2016Auger Muons and Infill for the Ground Array) is an upgrade of the Pierre Auger Observatory to extend its range of detection and to directly measure the muon content of the particle showers. It consists of an infill of surface water-Cherenkov detectors ... More
Search for correlations between the arrival directions of IceCube neutrino events and ultrahigh-energy cosmic rays detected by the Pierre Auger Observatory and the Telescope ArrayNov 30 2015Jan 21 2016This paper presents the results of different searches for correlations between very high-energy neutrino candidates detected by IceCube and the highest-energy cosmic rays measured by the Pierre Auger Observatory and the Telescope Array. We first consider ... More
Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger ObservatoryAug 18 2015Jun 20 2016The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which ... More
Groups of quasi-invariance and the Pontryagin dualityDec 09 2008Oct 01 2009A Polish group $G$ is called a group of quasi-invariance or a QI-group, if there exist a locally compact group $X$ and a probability measure $\mu$ on $X$ such that 1) there exists a continuous monomorphism of $G$ to $X$, and 2) for each $g\in X$ either ... More
The Higgs Boson Production Cross Section as a Precision Observable?Mar 06 2002Jul 30 2002We investigate what can be learned at a linear collider about the sector of electroweak symmetry breaking from a precise measurement of the Higgs boson production cross section through the process e+e- -> hZ. We focus on deviations from the Standard Model ... More
X-ray observations of cluster outskirts: current status and future prospectsMay 03 2010Dec 22 2010Past and current X-ray mission allow us to observe only a fraction of the volume occupied by the ICM. After reviewing the state of the art of cluster outskirts observations we discuss some important constraints that should be met when designing an experiment ... More
Lower and upper bounds on the mass of light quark-antiquark scalar resonance in the SVZ sum rulesMay 23 2016The calculation of the mass of light scalar isosinglet meson within the Shifman--Vainshtein--Zakharov (SVZ) sum rules is revisited. We develop simple analytical methods for estimation of hadron masses in the SVZ approach and try to reveal the origin of ... More
Low-energy holographic models for QCDFeb 01 2011Apr 09 2011We consider the bottom-up holographic models for QCD which contain the ultraviolet (UV) cutoff. Such models are supposed to describe exclusively the low-energy sector of QCD. The introduction of UV cutoff in the soft wall model is shown to result in a ... More
AdS/QCD models describing a finite number of excited mesons with Regge spectrumMar 02 2009The typical AdS/QCD models deal with the large-N_c limit of QCD, as a consequence the meson spectrum consists of the infinite number of states that is far from the real situation. Basing on introduction of anharmonic corrections to the holographic potential, ... More
Generalized Soft Wall ModelOct 18 2012Jan 27 2013We develop an exactly solvable generalization of the soft wall holographic model for the vector mesons. The generalization preserves the ultraviolet and infrared asymptotics of the soft wall model and contains an additional free parameter. This new parameter ... More
Comment on "Parity Doubling and SU(2)_L X SU(2)_R Restoration in the Hadronic Spectrum" and "Parity Doubling Among the Baryons"May 09 2006Some aspects of two recent papers on parity doubling in the hadronic spectrum and its relation to restoration of linearly realized chiral symmetry are critically discussed.
Steenrod operations and the diagonal morphismJul 04 2013Jan 15 2014We show how to find the Steenrod operations in H^*(X) (the coefficients in F_p) given the diagonal morphism d_#:S_*(X)->S_*(X^p) and the action of the cyclic group C_p on S_*(X^p). Our construction needs no other data such as Eilenberg-Zilber morphisms. ... More
Sobolev and Schwartz: Two Fates and Two FamesFeb 05 2008Feb 13 2008This is a brief overview of the lives and contributions of S.L. Sobolev and L. Schwartz, the cofounders of distribution theory.
The Game of Cipher BeadsMay 20 2009Jul 29 2009Comparison between the various impact factors of a few Russian journals demonstrates the deficiencies of the popular citation indices.
Pareto Optimality and IsoperimetryFeb 06 2009Under study is the new class of geometrical extremal problems in which it is required to achieve the best result in the presence of conflicting goals; e.g., given the surface area of a convex body $\mathfrak x$, we try to maximize the volume of $\mathfrak ... More
On Grothendieck SubspacesApr 04 2005The modulus of an order bounded functional on a Riesz space is the sum of a pair of Riesz homomorphisms if and only if the kernel of this functional is a Grothendieck subspace of the ambient Riesz space. An operator version of this fact is given.
Generalized Integral Siding Mode Manifold Design: A Sum of Squares ApproachMar 30 2015May 21 2015This paper presents a general form of integral sliding mode manifold, and proposes an algorithmic approach based on Sum of Squares (SOS) programming to design generalized integral sliding mode manifold and controller for nonlinear systems with both matched ... More
Di-photon Higgs signals at the LHC in the Next-to-Minimal Supersymmetric Standard ModelMar 10 2006The NMSSM contains a Higgs singlet in addition to the two Higgs doublets typical of the MSSM, thus resulting in a total of seven physical Higgs mass states. Therefore, the phenomenology of the NMSSM Higgs sector can vary considerably from that of the ... More
Shock Dissipation in Magnetically Dominated Impulsive FlowsJan 17 2012We have revisited the issue of shock dissipation and emission and its implications for the internal shock model of the prompt GRB emission and studied it in the context of impulsive Poynting-dominated flows. Our results show that unless the magnetization ... More
3+1 MagnetodynamicsAug 17 2011Aug 30 2011The Magnetodynamics, or Force-Free Degenerate Electrodynamics, is recognized as a very useful approximation in studies of magnetospheres of relativistic stars. In this paper we discuss various forms of Magnetodynamic equations which can be used to study ... More
Blandford-Znajek mechanism versus Penrose processApr 11 2008During the three decades since its theoretical discovery the Blandford-Znajek process of extracting the rotational energy of black holes has become one of the foundation stones in the building of modern relativistic astrophysics. However, it is also true ... More
Multi-dimensional Numerical Scheme for Resistive Relativistic MHDAug 02 2007The paper describes a new upwind conservative numerical scheme for special relativistic resistive magnetohydrodynamics with scalar resistivity. The magnetic field is kept approximately divergence free and the divergence of the electric field consistent ... More
The eta-photon transition form factorOct 28 2011Feb 08 2012The eta-photon transition form factor is evaluated in a formalism based on a phenomenological description at low values of the photon virtuality, and a QCD-based description at high photon virtualities, matching at a scale $Q_{0}^{2}$. The high photon ... More
Geometry of N=4, d=1 nonlinear supermultipletNov 09 2006We construct the general action for $N=4, d=1$ nonlinear supermultiplet including the most general interaction terms which depend on the arbitrary function $h$ obeying the Laplace equation on $S^3$. We find the bosonic field $B$ which depends on the components ... More
Random walks in a random environmentMar 05 2005Random walks as well as diffusions in random media are considered. Methods are developed that allow one to establish large deviation results for both the `quenched' and the `averaged' case.
Heavy charged Higgs boson production at next generation $γγ$ collidersNov 05 2002We investigate the scope of all relevant production modes of charged Higgs bosons in the MSSM, with mass larger than the one of the top quark, at future Linear Colliders operating in $\gamma\gamma$ mode at the TeV energy scale. Final states with one or ... More
A first-principles systematic study of GaAs nanowiresJan 22 2009Dec 23 2010In this paper we present a detailed analysis of the atomic and electronic structure of GaAs nanowires using first-principles pseudopotential calculations. We consider six different types of nanowires with different diameters all grown along [111] direction ... More
Electron-hole asymmetry in magnetic properties of lightly doped high-$T_{\rm C}$ superconductors: a quantum Monte Carlo studyAug 14 2003Using a recently developed variational quantum Monte Carlo method, magnetic properties of high-$T_{\rm C}$ superconductors are studied at zero temperature ($T$), by numerical simulations on the 2D t-J model. Our focus here is to explore the difference ... More
Boolean Models and Simultaneous InequalitiesJul 01 2009Aug 27 2009Boolean models are applied to deriving operator versions of the classical Farkas Lemma in the theory of simultaneous linear inequalities.
Expected Number of Local Maxima of Some Gaussian Random PolynomialsMay 04 2006Let $Q_n(x)=\sum_{i=0}^{n} A_{i}x^{i}$ be a random algebraic polynomial where the coefficients $A_0,A_1,... $ form a sequence of centered Gaussian random variables. Moreover, assume that the increments $\Delta_j=A_j-A_{j-1}$, $j=0,1,2,...$ are independent, ... More
Review and Analysis of The Issues of Unified Modeling Language for Visualizing, Specifying, Constructing and Documenting the Artifacts of a Software-Intensive SystemJan 23 2010The UML allows us to specify models in a precise, complete and unambiguous manner. In particular, the UML addresses the specification of all important decisions regarding analysis, design and implementation. Although UML is not a visual programming language, ... More
Reducing Polarization Mode Dispersion With Controlled Polarization RotationsJun 02 2006One of the fundamental limitations to high bit rate, long distance, telecommunication in optical fibers is Polarization Mode Dispersion (PMD). Here we introduce a conceptually new method to reduce PMD in optical fibers by carrying out controlled rotations ... More
Superconducting networks with the proximity effectNov 06 2009May 20 2011We report on the first observation of a novel type of superconducting proximity network using a superconductor-normal metal bilayer. Little-Parks oscillation measurements show that the superconducting current flows through a path enclosed by the edge ... More
An Observational Perspective of the IMF: Progress and ChallengesOct 20 2015The stellar initial mass function (IMF) is a fundamental astrophysical quantity that impacts a wide range of astrophysical problems from heavy element distribution to galactic evolution to planetary system formation. However, the origin and universality ... More
Oscillating structure of γ-bursts and their possible originMay 04 2000As it is well-known that the hydrodinamic collapse of the massive star iron core should lead to the production of a hot neutron star. The assumption is made that the thermonuclear burning of the envelope matter, accreting onto the hot neutron star, can ... More
The mass function of young star clusters in spiral galaxiesDec 07 2008Sep 23 2009The initial cluster mass function (ICMF) in spiral galaxy discs is constrained and compared with data for old globular clusters and young clusters in starbursts. It is found that the observed ages and luminosities of the brightest clusters in spiral discs ... More
Observational Constraints on Cluster EvolutionSep 04 2006Current observational constraints on the dynamical evolution of star clusters are reviewed. Theory and observations now agree nicely on the mass dependency and time scales for disruption of young star clusters in galactic disks, but many problems still ... More
EDM constraints and CP asymmetries of B processes in supersymmetric modelsDec 22 2004We demonstrate that electric dipole moments (EDMs) strongly constrain possible SUSY contributions to the CP asymmetries of B processes; LL and/or RR flavour mixings between second and third generations are severely restricted by the experimental limit ... More
Zero-Range Potentials in Multi-Channel Diatomic Molecule ScatteringMay 17 2002The method of zero-range potentials is generalized to account for the molecular electron excitation process. It is made by a matrix formulation in which a state vector components are associated with a scattering channel. The multi-center target is considered ... More
On the possibility of Casimir repulsion using MetamaterialsSep 15 2009It is well known that the Casimir force between two half-spaces is dictated by their electromagnetic properties. In particular, when one of the half-spaces is mainly metallic or dielectric and the other is mainly magnetic, it is possible to show that ... More
Quantisation of twistor theory by cocycle twistJan 30 2007Mar 20 2007We present the main ingredients of twistor theory leading up to and including the Penrose-Ward transform in a coordinate algebra form which we can then `quantise' by means of a functorial cocycle twist. The quantum algebras for the conformal group, twistor ... More
Finite-size effects on the Hamiltonian dynamics of the XY-modelMay 31 2001The dynamical properties of the finite-size magnetization M in the critical region T<T_{KTB} of the planar rotor model on a L x L square lattice are analyzed by means of microcanonical simulations . The behavior of the q=0 structure factor at high frequencies ... More
Light-front $φ^4_{1+1}$ theory using a many-boson symmetric-polynomial basisDec 29 2015We extend earlier work on fully symmetric polynomials for three-boson wave functions to arbitrarily many bosons and apply these to a light-front analysis of the low-mass eigenstates of $\phi^4$ theory in 1+1 dimensions. The basis-function approach allows ... More
Application of a light-front coupled-cluster method to quantum electrodynamicsJun 26 2012A field-theoretic formulation of the exponential-operator technique is applied to a Hamiltonian eigenvalue problem in electrodynamics, quantized in light-front coordinates. Specifically, we consider the dressed-electron state, without positron contributions ... More
Estimation of Effort in Software Cost Analysis for Heterogenous Dataset using Fuzzy AnalogyNov 06 2012One of the significant objectives of software engineering community is to use effective and useful models for precise calculation of effort in software cost estimation. The existing techniques cannot handle the dataset having categorical variables efficiently ... More
Magnetization induced by odd-frequency spin-triplet Cooper pairs in a Josephson junction with metallic trilayersJul 14 2015We theoretically study the magnetization inside a normal metal induced in an s-wave superconductor/ferromagnetic metal/normal metal/ferromagnetic metal/s-wave superconductor (S/F1/N/F2/S) Josephson junction. Using quasiclassical Green's function method, ... More
Relativistic Toda chain at root of unityJan 15 2001May 17 2001We declare briefly several interesting features of the quantum relativistic Toda chain at N-th root of unity. We consider the finite dimensional representation of the Weyl algebra. The origin of the features mentioned is that we consider simultaneously ... More
Spin Injection and Detection in Magnetic NanostructuresDec 13 2002We study theoretically the spin transport in a nonmagnetic metal connected to ferromagnetic injector and detector electrodes. We derive a general expression for the spin accumulation signal which covers from the metallic to the tunneling regime. This ... More
Black Holes and Naked Singularities in Low Energy Limit of String Gravity with Modulus FieldSep 11 2000Mar 16 2001We show that the black hole solutions of the effective string theory action, where one-loop effects that couple the moduli to gravity via a Gauss-Bonnet term are taken into account, admit primary scalar hair. The requirement of absence of naked singularities ... More
Abelian Cascade Dynamics in Bootstrap PercolationJul 27 1998The culling process in Bootstrap Percolation is Abelian since the final stable configuration does not depend on the details of the updating procedure. An efficient algorithm is devised using this idea for the determination of the bootstrap percolation ... More
Event-Driven Molecular Dynamics in ParallelFeb 03 2003Sep 16 2003Although event-driven algorithms have been shown to be far more efficient than time-driven methods such as conventional molecular dynamics, they have not become as popular. The main obstacle seems to be the difficulty of parallelizing event-driven molecular ... More
Band dispersion and electronic lifetimes in crystalline organic semiconductorsJan 11 2011Mar 31 2011The consequences of several microscopic interactions on the photoemission spectra of crystalline organic semiconductors (OSC) are studied theoretically. It is argued that their relative roles can be disentangled by analyzing both their temperature and ... More
Band-like motion and mobility saturation in organic molecular semiconductorsOct 22 2009Dec 07 2009We analyze a model that accounts for the inherently large thermal lattice fluctuations associated to the weak van der Waals inter-molecular bonding in crystalline organic semiconductors. In these materials the charge mobility generally exhibits a "metallic-like" ... More
Optical properties of small polarons from dynamical mean-field theoryDec 09 2005Feb 27 2006The optical properties of polarons are studied in the framework of the Holstein model by applying the dynamical mean-field theory. This approach allows to enlighten important quantitative and qualitative deviations from the limiting treatments of small ... More
Hopping dynamics of interacting polaronsOct 02 2008We derive an effective cluster model to address the transport properties of mutually interacting small polarons. We propose a decoupling scheme where the hopping dynamics of any given particle is determined by separating out explicitly the degrees of ... More
Derivative-based global sensitivity measures and their link with Sobol sensitivity indicesMay 25 2016The variance-based method of Sobol sensitivity indices is very popular among practitioners due to its efficiency and easiness of interpretation. However, for high-dimensional models the direct application of this method can be very time consuming and ... More
Metric-affine $f(R)$-gravity with torsion: an overviewOct 27 2009Torsion and curvature could play a fundamental role in explaining cosmological dynamics. f(R)-gravity with torsion is an approach aimed to encompass in a comprehensive scheme all the Dark Side of the Universe (Dark Energy and Dark Matter). We discuss ... More
Semiclassical limit for nonlinear Schroedinger equations with electromagnetic fieldsJul 06 2001Aug 21 2002We prove some multiplicity results by means of a perturbation technique in critical point theory.
Ito diffusions, modified capacity and harmonic measure. Applications to Schrodinger operatorsDec 17 2010Using certain Ito's equation, we introduce the probability on the space of paths and show its relevance to the scattering properties of multidimensional Schrodinger operator. To relate the geometry of the support of potential to the spectral type we develop ... More
Growth kinetic study of sputter deposition: Ag on Si/SiO$_2$Sep 11 2001Nov 30 2001We have presented the kinetic study of the very initial growth stages of an ultra thin film (40 $\AA$- 150$\AA$) of Ag sputter-deposited on Si(001) substrate containing native oxide using grazing incidence x-ray reflectivity (GIXR) technique and Atomic ... More
Effect of Diorder on the Peak Effect and Structure of Flux Line Lattice in 2H-NbSe2Sep 16 1997The effect of disorder on flux line lattice (FLL) melting is studied via the Peak Effect phenomenon. On the upper branch of the Peak Effect curve, where this effect is more robust, we observe a stepwise disordering of the FLL, suggesting two first order ... More
Threshold Based Indexing of Commercial Shoe Print to Create Reference and Recovery ImagesJan 29 2010One of the important evidence in a crime scene that is normally overlooked but very important evidence is shoe print as the criminal is normally unaware of the mask for this. In this paper we use image processing technique to process reference shoe images ... More
On topological properties of the group of the null sequences valued in an Abelian topological groupJun 21 2013Dec 09 2013Following [23], denote by $\mathfrak{F}_0$ the functor on the category $\mathbf{TAG}$ of all Hausdorff Abelian topological groups and continuous homomorphisms which passes each $X\in \mathbf{TAG}$ to the group of all $X$-valued null sequences endowed ... More
Bouvier's conjectureNov 28 2008This paper deals with Bouvier's conjecture which sustains that finite-dimensional non-Noetherian Krull domains need not be Jaffard