Results for "F. Agostini"

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The adiabatic limit of the exact factorization of the electron-nuclear wave functionApr 18 2016Jul 18 2016We propose a procedure to analyze the relation between the exact factorization of the electron-nuclear wave function and the Born-Oppenheimer approximation. We define the adiabatic limit as the limit of infinite nuclear mass. To this end, we introduce ... More
An Exact Factorization Perspective on Quantum Interferences in Nonadiabatic DynamicsApr 08 2016Jun 30 2016Nonadiabatic quantum interferences emerge whenever nuclear wavefunctions in different electronic states meet and interact in a nonadiabatic region. In this work, we analyze how nonadiabatic quantum interferences translate in the context of the exact factorization ... More
Ising Spin Glasses on Wheatstone-Bridge Hierarchical LatticesFeb 10 2010Nearest-neighbor-interaction Ising spin glasses are studied on three different hierarchical lattices, all of them belonging to the Wheatstone-Bridge family. It is shown that the spin-glass lower critical dimension in these lattices should be greater than ... More
Hopf-algebra description of noncommutative-spacetime symmetriesSep 01 2003I give a brief summary of the results reported in hep-th 0306013 in collaboration with G. Amelino-Camelia and F. D'Andrea. I focus on the analysis of the symmetries of $\kappa$-Minkowski noncommutative space-time, described in terms of a Weyl map. The ... More
kappa-Minkowski representations on Hilbert spacesDec 09 2005Jun 15 2007The algebra of functions on kappa-Minkowski noncommutative spacetime is studied as algebra of operators on Hilbert spaces. The representations of this algebra are constructed and classified. This new approach leads to a natural construction of integration ... More
Covariant formulation of Noether's Theorem for translations on kappa-Minkowski spacetimeNov 06 2007Apr 11 2009The problem of finding a formulation of Noether's theorem in noncommutative geometry is very important in order to obtain conserved currents and charges for particles in noncommutative spacetimes. In this paper, we formulate Noether's theorem for translations ... More
Fields and symmetries in $κ$-Minkowski noncommutative spacetimeDec 29 2003We have investigated some issues relevant for the possibility to construct physical theories on the $\kappa$-Minkowski noncommutative spacetime. The notion of field in $\kappa$-Minkowski has been introduced by generalizing the Weyl system/map formalism ... More
A note on homogeneous ideals of polarized abelian surfacesApr 21 2016May 06 2016Gross and Popescu conjectured that the homogeneous ideal of an embedded $(1,d)$-polarized abelian surface is generated by quadrics and cubics for $d\geq 9$. We prove this using the projective normality of the embedding. It follows that the homogeneous ... More
Consequences of vacuum polarization on electromagnetic waves in a Lorentz-symmetry breaking scenarioJul 19 2011Jan 20 2012The propagation of electromagnetic waves in a Lorentz-symmetry violating scenario where there is a region of polarized vacuum is studied. It turns out that the photon field acquires an interesting polarization state, possibly useful to set up upper bounds ... More
Statistical features of edge turbulence in RFX-mod from Gas Puffing ImagingJun 30 2006Plasma density fluctuations in the edge plasma of the RFX-mod device are measured through the Gas Puffing Imaging Diagnostics. Statistical features of the signal are quantified in terms of the Probability Distribution Function (PDF), and computed for ... More
Inelastic scattering of broadband electron wave packets driven by an intense mid-infrared laser fieldSep 01 2011Intense, 100 fs laser pulses at 3.2 and 3.6 um are used to generate, by multi-photon ionization, broadband wave packets with up to 400 eV of kinetic energy and charge states up to Xe+6. The multiple ionization pathways are well described by a white electron ... More
About the parabolic relation existing between the skewness and the kurtosis in time series of experimental dataFeb 12 2009In this work we investigate the origin of the parabolic relation between skewness and kurtosis often encountered in the analysis of experimental time-series. We argue that the numerical values of the coefficients of the curve may provide informations ... More
Cell-centric heuristics for the classification of cellular automataAug 06 2004We study the classification of cellular-automaton update rules into Wolfram's four classes. We start with the notion of the input entropy of a spatiotemporal block in the evolution of a cellular automaton, and build on it by introducing two novel entropy ... More
2000 CKM-Triangle Analysis A Critical Review with Updated Experimental Inputs and Theoretical ParametersDec 22 2000Mar 09 2001Within the Standard Model, a review of the current determination of the sides and angles of the CKM unitarity triangle is presented, using experimental constraints from the measurements of |\epsilon_K|, |V_{ub}/V_{cb}|, \Delta m_d and from the limit on ... More
Attosecond pulse shaping around a Cooper minimumOct 25 2013High harmonic generation (HHG) is used to measure the spectral phase of the recombination dipole matrix element (RDM) in argon over a broad frequency range that includes the 3p Cooper minimum (CM). The measured RDM phase agrees well with predictions based ... More
Learning about probabilistic inference and forecasting by playing with multivariate normal distributionsApr 08 2015The properties of the normal distribution under linear transformation, as well the easy way to compute the covariance matrix of marginals and conditionals, offer a unique opportunity to get an insight about several aspects of uncertainties in measurements. ... More
Bertrand `paradox' reloaded (with details on transformations of variables, an introduction to Monte Carlo simulation and an inferential variation of the problem)Apr 06 2015This note is mainly to point out, if needed, that uncertainty about models and their parameters has little to do with a `paradox'. The proposed `solution' is to formulate practical questions instead of seeking refuge into abstract principles. (And, in ... More
BitCracker: BitLocker meets GPUsJan 04 2019BitLocker is a full-disk encryption feature available in recent Windows versions. It is designed to protect data by providing encryption for entire volumes and it makes use of a number of different authentication methods. In this paper we present a solution, ... More
Discrete Gaussian distributions via theta functionsJan 08 2018Nov 28 2018We study a discrete analogue of the classical multivariate Gaussian distribution. It is supported on the integer lattice and is parametrized by the Riemann theta function. Over the reals, the discrete Gaussian is characterized by the property of maximizing ... More
Probably a discovery: Bad mathematics means rough scientific communicationDec 15 2011Dec 19 2011According to the media, in spring of this year the experiment CDF at Fermilab has made most likely ("this result has a 99.7 percent chance of being correct", Discovery News) a great discovery ("the most significant in physics in half a century", NYT). ... More
On the Japanese Multiplication Method. A father-and-daughter dialogueFeb 07 2018Recently the media broadcast the news, together with illustrative videos, of a so-called Japanese method to perform multiplication by hand without using the multiplication tables. "Goodbye multiplication tables" was the headline of several websites, including ... More
On bisequentiality and spaces of strictly decreasing functions on treesSep 05 2018We present a characterization of spaces of strictly decreasing functions on trees in terms of bisequentiality. This characterization answers Questions 6.1 and 6.2 of "A filter on a collection of finite sets and Eberlein compacta" by T. Cie\'sla. Moreover ... More
The Waves and the Sigmas (To Say Nothing of the 750 GeV Mirage)Sep 06 2016This paper shows how p-values do not only create, as well known, wrong expectations in the case of flukes, but they might also dramatically diminish the `significance' of most likely genuine signals. As real life examples, the 2015 first detections of ... More
Constraining the Higgs boson mass through the combination of direct search and precision measurement resultsJan 26 2000We show that the likelihood ratio of Higgs search experiments is a form to report the experimental results suitable to be combined with the information from precision measurements to obtain a joint constraint on the Higgs mass. We update our previous ... More
Constraints on the Higgs Boson Mass from Direct Searches and Precision MeasurementsFeb 02 1999We combine, within the framework of the Standard Model, the results of Higgs search experiments with the information coming from accurate theoretical calculation and precision measurements to provide a probability density function for the Higgs mass, ... More
Positive-Overlap Transition and Critical Exponents in Mean Field Spin GlassesSep 11 2006Nov 02 2006In this paper we obtain two results for the Sherrington-Kirkpatrick (SK) model, and we show that they both emerge from a single approach. First, we prove that the average of the overlap takes positive values when it is non zero. More specificly, the average ... More
Bigravity as an interpretation of the cosmic accelerationDec 01 2007Dec 06 2007A bimetric description of the universe is proposed, which explains cosmic acceleration deduced from optically observed high-redshift objects. This phenomenon is classically charged to a mysterious repulsive "dark energy" whose true nature is unknown. ... More
Probabilistic interpretation of the wave function for the Bianchi I modelApr 27 2017Jun 21 2017We compare two different approaches for quantization of the Bianchi I model: a reduced phase space quantization, in which the isotropic Misner variables is taken as time, and the Vilenkin proposal, in which a semiclassical approximation is performed for ... More
Probing flavor models with Ge-76-based experiments on neutrinoless double-beta decayJun 19 2015The physics impact of a staged approach for double-beta decay experiments based on Ge-76 is studied. The scenario considered relies on realistic time schedules envisioned by the GERDA and the MAJORANA collaborations, which are jointly working towards ... More
Bigravity: a bimetric model of the Universe with variable constants, inluding VSL (variable speed of light)Mar 10 2008Mar 15 2008The Universe, far to be homogenous, expands in large empty bubbles of the large-scale structure, but not in mass concentrations like galaxies, so that the Robertson-Walker solution does not fit. We suggest that a symmetry breaking occurred in a distant ... More
Generalized Weyl systems and kappa-Minkowski spaceSep 20 2002Nov 11 2002We introduce the notion of generalized Weyl system, and use it to define *-products which generalize the commutation relations of Lie algebras. In particular we study in a comparative way various *-products which generalize the k-Minkowski commutation ... More
Bigravity : A bimetric model of the Universe. Positive and negative gravitational lensingsJan 09 2008After a short summary of our bimetric model of the Universe, an exact nonlinear solution is built, which demonstrates the existence of solutions for our two coupled field equations system. In addition to the classical positive gravitational lensing, this ... More
Discovery probability of next-generation neutrinoless double-$β$ decay experimentsMay 08 2017Jul 21 2017The Bayesian discovery probability of future experiments searching for neutrinoless double-$\beta$ decay is evaluated under the popular assumption that neutrinos are their own antiparticles. A Bayesian global fit is performed to construct a probability ... More
Higher syzygies on surfaces with numerically trivial canonical bundleMar 29 2017We characterize property $(N_p)$ on a polarized surface $(X,L)$ with trivial canonical bundle in terms of the (non)existence of certain forbidden subvarieties of $X$.
Off-line data processing and analysis for the GERDA experimentNov 15 2011GERDA is an experiment designed to look for the neutrinoless double beta decay of Ge-76. The experiment uses an array of high-purity germanium detectors, enriched in Ge-76, directly immersed in liquid argon. GERDA is presently operating eight enriched ... More
Five Dimensional bigravity. New topological description of the UniverseMay 09 2008We extend the bimetric description of the Universe to a five-dimensional framework. Starting from Souriau's work (1964) we use two Robertson-Walker metrics with an extra term corresponding to the additional Kaluza fifth dimension. This first order model ... More
Dirac spinors for Doubly Special Relativity and $κ$-Minkowski noncommutative spacetimeJun 29 2002Dec 09 2003We construct a Dirac equation that is consistent with one of the recently-proposed schemes for a "doubly-special relativity", a relativity with both an observer-independent velocity scale (still naturally identified with the speed-of-light constant) and ... More
Non-eikonal corrections to multi-particle production in the Color Glass CondensateFeb 12 2019We consider the non-eikonal corrections to particle production in the Color Glass Condensate stemming from the relaxation of the shockwave approximation for the target that acquires a finite longitudinal dimension. We derive a modified expression of the ... More
On the statistics of edge fluctuations: comparative study between various fusion devicesFeb 12 2009In this paper we present a statistical study of edge fluctuations taken with the Gas Puffing Imaging (GPI) diagnostics. We carry out a comparison of GPI signal from an extensive database including four devices (two Tokamaks and two Reversed Field Pinches). ... More
Speeding up complex multivariate data analysis in Borexino with parallel computing based on Graphics Processing UnitMay 28 2018A spectral fitter based on the graphics processor unit (GPU) has been developed for Borexino solar neutrino analysis. It is able to shorten the fitting time to a superior level compared to the CPU fitting procedure. In Borexino solar neutrino spectral ... More
Improved measurement of 8B solar neutrinos with 1.5 kt y of Borexino exposureSep 03 2017We report on an improved measurement of the $^8$B solar neutrino interaction rate with the Borexino detector at the Laboratori Nazionali del Gran Sasso. Neutrinos are detected via their elastic scattering on electrons in a large, radio-pure liquid scintillator ... More
The large-angle photon veto system for the NA62 experiment at the CERN SPSJul 25 2012The branching ratio (BR) for the decay K^+ \to \pi^+\nu\bar{\nu} is a sensitive probe for new physics. The NA62 experiment at the CERN SPS will measure this BR to within about 10%. To reject the background from dominant kaon decays with final state photons, ... More
GELATIO: a general framework for modular digital analysis of high-purity Ge detector signalsJun 09 2011GELATIO is a new software framework for advanced data analysis and digital signal processing developed for the GERDA neutrinoless double beta decay experiment. The framework is tailored to handle the full analysis flow of signals recorded by high purity ... More
Interference effects in two-photon ATI by multiple orders high harmonics with random or locked phasesSep 07 1998Jan 18 1999We numerically study 2-photon processes using a set of harmonics from a Ti:Sapphire laser and in particular interference effects in the Above Threshold Ionization spectra. We compare the situation where the harmonic phases are assumed locked to the case ... More
I - Matter, antimatter and geometry II - The twin universe model : a solution to the problem of negative energy particles III - The twin universe model plus electric charges and matter-antimatter symmetryFeb 20 2005Mar 09 2005We introduce a new dynamical group whose coadjoint action on its momentum space takes account of matter-antimatter symmetry on pure geometrical grounds. According to this description the energy and the spin are unchanged under matter-antimatter symmetry. ... More
Maximum probability domains for the analysis of the microscopic structure of liquidsSep 07 2014Jan 04 2015We introduce the concept of maximum probability domains (MPDs), developed in the context of the analysis of electronic densities, in the study of the microscopic spatial structures of liquids. The idea of locating a particle in a three dimensional region, ... More
A coupled-trajectory quantum-classical approach to decoherence in non-adiabatic processesApr 01 2015Jun 27 2015We present a novel quantum-classical approach to non-adiabatic dynamics, deduced from the coupled electronic and nuclear equations in the framework of the exact factorization of the electron-nuclear wave function. The method is based on the quasi-classical ... More
Mixed quantum-classical dynamics from the exact decomposition of electron-nuclear motionFeb 26 2014Feb 27 2014We present a novel mixed quantum-classical approach to the coupled electron-nuclear dynamics based on the exact factorization of the electron-nuclear wave function, recently proposed in [A. Abedi, N. T. Maitra, and E. K. U. Gross, Phys. Rev. Lett. 105, ... More
The NA62 LAV front-end electronicsNov 24 2011The branching ratio for the decay $K^+ \to \pi^+\nu\bar{\nu}$ is sensitive to new physics; the NA62 experiment will measure it to within about 10%. To reject the dominant background from channels with final state photons, the large-angle vetoes (LAVs) ... More
Mixed quantum-classical dynamics on the exact time-dependent potential energy surface: A fresh look at non-adiabatic processesJul 01 2013The exact nuclear time-dependent potential energy surface arises from the exact decomposition of electronic and nuclear motion, recently presented in [A. Abedi, N. T. Maitra, and E. K. U. Gross, Phys. Rev. Lett. 105, 123002 (2010)]. Such time-dependent ... More
The Large-Angle Photon Veto System for the NA62 Experiment at CERNNov 17 2011The branching ratio (BR) for the decay K^+ \rightarrow \pi^+ \nu \bar{\nu} is a sensitive probe for new physics. The NA62 experiment at the CERN SPS will measure this BR to within about 10%. To reject the dominant background from channels with final state ... More
Search for correlation between GRB's detected by BeppoSAX and gravitational wave detectors EXPLORER and NAUTILUSJun 25 2002Jul 12 2002Data obtained during five months of 2001 with the gravitational wave (GW) detectors EXPLORER and NAUTILUS were studied in correlation with the gamma ray burst data (GRB) obtained with the BeppoSAX satellite. During this period BeppoSAX was the only GRB ... More
The Spectrum of the 2+1 Dimensional Gauge Ising ModelJul 11 1996We present a high precision Monte Carlo study of the spectrum of the $Z_2$ gauge theory in $2+1$ dimensions in the strong coupling phase. Using state of the art Monte Carlo techniques we are able to accurately determine up to three masses in a single ... More
Semiclassical analysis of the electron-nuclear coupling in electronic non-adiabatic processesJan 31 2015Mar 30 2015In the context of the exact factorization of the electron-nuclear wave function, the coupling between electrons and nuclei beyond the adiabatic regime is encoded (i) in the time-dependent vector and scalar potentials and (ii) in the electron-nuclear coupling ... More
Classical nuclear motion coupled to electronic non-adiabatic transitionsJun 19 2014We present a detailed derivation and numerical tests of a new mixed quantum-classical scheme to deal with non-adiabatic processes. The method is presented as the zero-th order approximation to the exact coupled dynamics of electrons and nuclei offered ... More
Steps in the exact time-dependent potential energy surfaceFeb 06 2013We study the exact Time-Dependent Potential Energy Surface (TDPES) in the presence of strong non-adiabatic coupling between the electronic and nuclear motion. The concept of the TDPES emerges from the exact factorization of the full electron-nuclear wave-function ... More
Bayesian model comparison applied to the Explorer-Nautilus 2001 coincidence dataApr 24 2003Jun 16 2003Bayesian reasoning is applied to the data by the ROG Collaboration, in which gravitational wave (g.w.) signals are searched for in a coincidence experiment between Explorer and Nautilus. The use of Bayesian reasoning allows, under well defined hypotheses, ... More
NLO-QCD corrections to Higgs pair production in the MSSMJan 14 2016Apr 18 2016We take a step towards a complete NLO-QCD determination of the production of a pair of Higgs scalars in the MSSM. Exploiting a low-energy theorem that connects the Higgs-gluon interactions to the derivatives of the gluon self-energy, we obtain analytic ... More
Action functional for kappa-Minkowski Noncommutative SpacetimeJul 27 2004We examine some alternative possibilities for an action functional for $\kappa$-Minkowski noncommutative spacetime, with an approach which should be applicable to other spacetimes with coordinate-dependent commutators of the spacetime coordinates ($[x_\mu,x_\nu]=f_{\mu,\nu}(x)$). ... More
Hopf-algebra description of noncommutative-spacetime symmetriesJun 03 2003Jun 21 2003In the study of certain noncommutative versions of Minkowski spacetime there is still a large ambiguity concerning the characterization of their symmetries. Adopting as our case study the kappaMinkowski noncommutative space-time, on which a large literature ... More
On evidence for negative energies and masses in the Dirac equation through a unitary time-reversal operatorSep 12 2018Nov 07 2018We review the standards of relativistic quantum mechanics such as the Dirac equation under the concept of negative masses. We show that negative energies are acceptable provided the masses are simultaneously negative. Negative energy and mass anti fermions ... More
The maximum likelihood degree of Fermat hypersurfacesApr 23 2014Apr 08 2015We study the critical points of the likelihood function over the Fermat hypersurface. This problem is related to one of the main problems in statistical optimization: maximum likelihood estimation. The number of critical points over a projective variety ... More
Developing Structural, High-heat flux and Plasma Facing Materials for a near-term DEMO Fusion Power Plant: the EU AssessmentAug 14 2014The findings of the EU 'Materials Assessment Group' (MAG), within the 2012 EU Fusion Roadmap exercise, are discussed. MAG analysed the technological readiness of structural, plasma facing and high heat flux materials for a DEMO concept to be constructed ... More
Multiphysics simulation of corona discharge induced ionic windJun 27 2013Ionic wind devices or electrostatic fluid accelerators are becoming of increasing interest as tools for thermal management, in particular for semiconductor devices. In this work, we present a numerical model for predicting the performance of such devices, ... More
Quantum-Classical Non-Adiabatic Dynamics: Coupled- vs. Independent-Trajectory MethodsDec 15 2015Feb 26 2016Trajectory-based mixed quantum-classical approaches to coupled electron-nuclear dynamics suffer from well-studied problems such as the lack of (or incorrect account for) decoherence in the trajectory surface hopping method and the inability of reproducing ... More
Photoionization Delay in He, Ne, Ar and KrJul 13 2013Jul 31 2013We study the relative photoionization delay of Ne, Ar and Kr as a function of energy using He as a reference to characterize or XUV pulse.
On the mass of atoms in molecules: Beyond the Born-Oppenheimer approximationMay 13 2016Jul 15 2016Describing the dynamics of nuclei in molecules requires a potential energy surface, which is traditionally provided by the Born-Oppenheimer or adiabatic approximation. However, we also need to assign masses to the nuclei. There, the Born-Oppenheimer picture ... More
Nuclear velocity perturbation theory for vibrational circular dichroism: An approach based on the exact factorization of the electron-nuclear wave functionMay 16 2015Aug 03 2015The nuclear velocity perturbation theory (NVPT) for vibrational circular dichroism (VCD) is derived from the exact factorization of the electron-nuclear wave function. This new formalism offers an exact starting point to include correction terms to the ... More
The exact forces on classical nuclei in non-adiabatic charge transferJun 18 2014Jan 31 2015The decomposition of electronic and nuclear motion presented in~[A. Abedi, N. T. Maitra, and E. K. U. Gross, Phys. Rev. Lett. 105, 123002 (2010)] yields a time-dependent potential that drives the nuclear motion and fully accounts for the coupling to the ... More
Generalizing the Noether theorem for Hopf-algebra spacetime symmetriesJul 27 2006Jan 25 2007Over these past few years several quantum-gravity research groups have been exploring the possibility that in some Planck-scale nonclassical descriptions of spacetime one or another form of nonclassical spacetime symmetries might arise. One of the most ... More
Off-line data quality monitoring for the GERDA experimentNov 30 2011GERDA is an experiment searching for the neutrinoless {\beta}{\beta} decay of Ge-76. The experiment uses an array of high-purity germanium detectors, enriched in Ge-76, directly immersed in liquid argon. GERDA recently started the physics data taking ... More
A Multiscale Thermo-Fluid Computational Model for a Two-Phase Cooling SystemApr 02 2014In this paper, we describe a mathematical model and a numerical simulation method for the condenser component of a novel two-phase thermosyphon cooling system for power electronics applications. The condenser consists of a set of roll-bonded vertically ... More
SU(2)-spin Invariant Auxiliary Field Quantum Monte Carlo Algorithm for Hubbard modelsJun 25 1998Auxiliary field quantum Monte Carlo methods for Hubbard models are generally based on a Hubbard-Stratonovitch transformation where the field couples to the z-component of the spin. This transformation breaks SU(2) spin invariance. The symmetry is restored ... More
Adiabatic Magnetization of Superconductors as a High-Performance Cooling MechanismNov 25 2008The adiabatic magnetization of a superconductor is a cooling principle proposed in the 30s, which has never been exploited up to now. Here we present a detailed dynamic description of the effect, computing the achievable final temperatures as well as ... More
Hybrid superconducting quantum magnetometerMar 18 2011Dec 03 2011A superconducting quantum magnetometer based on magnetic flux-driven modulation of the density of states of a proximized metallic nanowire is theoretically analyzed. With optimized geometrical and material parameters transfer functions up to a few mV/Phi_0 ... More
Long-Time Correlations in the Stochastic RegimeJan 11 2005The phase space for Hamiltonians of two degrees of freedom is usually divided into stochastic and integrable components. Even when well into the stochastic regime, integrable orbits may surround small stable regions or islands. The effect of these islands ... More
Temporal Evolution of Lower Hybrid Waves in the Presence of Ponderomotive Density FluctuationsJan 10 2005The propagation of lower hybrid waves in the presence of ponderomotive density fluctuations is considered. The problem is treated in two dimensions and, in order to be able to correctly impose the boundary conditions, the waves are allowed to evolve in ... More
Algorithms for geodesicsSep 21 2011Mar 28 2012Algorithms for the computation of geodesics on an ellipsoid of revolution are given. These provide accurate, robust, and fast solutions to the direct and inverse geodesic problems and they allow differential and integral properties of geodesics to be ... More
Stochastic Optimal Control with Delay in the Control I: solving the HJB equation through partial smoothingJul 21 2016Stochastic optimal control problems governed by delay equations with delay in the control are usually more difficult to study than the the ones when the delay appears only in the state. This is particularly true when we look at the associated Hamilton-Jacobi-Bellman ... More
Right-Left Asymmetry of Radiation from FissionOct 09 2007The effect of the right-left asymmetry is considered in the predicted earlier electric dipole radiation from fission fragments arising due to the Strutinski-Denisov induced polarisation mechanism. The magnitude of the asymmetry parameter is on the level ... More
Gas accretion on spiral galaxies: bar formation and renewalJun 17 2002The effects of gas accretion on spiral disk dynamics and stability are studied through N-body simulations, including star formation and gas/stars mass exchange. The detailed processes of bar formation, bar destruction and bar re-formation are followed, ... More
Formation of polar ring galaxiesJan 20 2003Feb 04 2003Polar ring galaxies are peculiar systems in which a gas rich, nearly polar ring surrounds an early-type or elliptical host galaxy. Two formation scenarios for these objects have been proposed: they are thought to form either in major galaxy mergers or ... More
FCNC production of same sign Top quark pairs at the LHCNov 05 2003Nov 06 2003We study the possibility of same sign top quark pair production at the LHC (and the VLHC) as a direct probe of FCNC processes. Besides the SM neutral Z boson, two other neutral bosons are considered, a top-Higgs type scalar and a Z' boson that appear ... More
UHECRs from the Radio Lobes of AGNsSep 23 2008Oct 07 2008We report a stochastic mechanism of particle acceleration from first principles in an environment having properties like those of Radio Lobes in AGNs. We show that energies $\sim 10^{20}$ eV are reached in $\sim 10^6$ years for protons. Our results reopen ... More
Taub, Rindler, and the static plateFeb 03 2005An infinite 3D plate of homogeneous incompressible fluid is considered, with finite thickness, together with a 2D infinite homogeneous mass in its centre. Einstein equations are exactly solved, in the interior of the 3D mass. The solution is joined to ... More
Separations inside a cubeDec 28 2001Two points are randomly selected inside a three-dimensional euclidian cube. The value l of their separation lies somewhere between zero and the length of a diagonal of the cube. The probability density P(l) of the separation is obtained analytically. ... More
Cosmic crystallography in a circleMay 15 2000Oct 05 2000In a circle (an S^1) with circumference 1 assume m objects distributed pseudo-randomly. In the universal covering R^1 assume the objects replicated accordingly, and take an interval L>1. In this interval, make the normalized histogram of the pair separations ... More
Synchronization of non-chaotic dynamical systemsAug 09 1999Dec 14 2000A synchronization mechanism driven by annealed noise is studied for two replicas of a coupled-map lattice which exhibits stable chaos (SC), i.e. irregular behavior despite a negative Lyapunov spectrum. We show that the observed synchronization transition, ... More
tbW vertex in the Littlest Higgs Model with T-parityOct 27 2008Feb 12 2009A study of the effective tbW vertex is done in the littlest Higgs model with T parity that includes the one loop induced weak dipole coefficient f_{2R}. The top's width, the W-boson helicity in the t-> bW^+ decay as well as the t-channel and the s-channel ... More
Non-Statistical gamma Rays from FragmentsOct 09 2007Polarization mechanism by Strutinsky-Denisov gives rise to the electric dipole radiation from fragments. Its probability calculated within the LDM turns out to be ~3.5x10-2 per fission. The radiation occurs during thermolization of the post-rupture deformation ... More
Stochastic Optimal Control with Delay in the Control II: Verification Theorem and Optimal FeedbacksJul 21 2016We consider a stochastic optimal control problem governed by a stochastic differential equation with delay in the control. Using a result of existence and uniqueness of a sufficiently regular mild solution of the associated Hamilton-Jacobi-Bellman (HJB) ... More
Measurement of wave-particle interaction and metastable lifetime using laser-induced fluorescenceFeb 27 2019Extensive information, such as ion temperature and wave-particle interactions, can be obtained by direct measurement of ion distribution functions using laser-induced fluorescence (LIF). This nonintrusive plasma diagnostic provides an important window ... More
A hyperbolic analog of the phasor addition formulaNov 20 2014Feb 23 2017In this article we review the basics of the phasor formalism in a rigorous way, highlighting the physical motivation behind it and presenting a hyperbolic counterpart of the phasor addition formula.
Depleted Kondo LatticesApr 07 2001Nov 17 2001We consider a two dimensional Kondo lattice model with exchange J and hopping t in which three out of four impurity spins are removed in a regular way. At the particle-hole symmetric point the model may be studied with auxiliary field quantum Monte Carlo ... More
The interplay between d-wave superconductivity and antiferromagnetic fluctuations: a quantum Monte Carlo studyJun 25 1998We consider the repulsive Hubbard model on a square lattice with an additional term, W, which depends upon the square of a single-particle nearest-neighbor hopping. At half-band filling, constant W, we show that enhancing U/t drives the system from a ... More
Superconductors as ideal spin sources for spintronicsNov 05 2007Apr 03 2008Spin-polarized transport is investigated in normal metal-superconductor (NS) junctions as a function of interface transmissivity as well as temperature when the density of states of a superconductor is Zeeman-split in response to an exchange field (h_exc). ... More
Ultra-High-Energy Cosmic Rays from the Radio Lobes of AGNsSep 22 2008In the past year, the HiRes and Auger collaborations have reported the discovery of a high-energy cutoff in the ultra-high energy cosmic-ray (UHECR) spectrum, and an apparent clustering of the highest energy events towards nearby active galactic nuclei ... More
Sampling exactly from the normal distributionMar 25 2013Jun 10 2014An algorithm for sampling exactly from the normal distribution is given. The algorithm reads some number of uniformly distributed random digits in a given base and generates an initial portion of the representation of a normal deviate in the same base. ... More
Transverse Mercator with an accuracy of a few nanometersFeb 08 2010Feb 03 2011Implementations of two algorithms for the transverse Mercator projection are described; these achieve accuracies close to machine precision. One is based on the exact equations of Thompson and Lee and the other uses an extension of Krueger's series for ... More
Quaternions in molecular modelingJun 23 2005Apr 04 2006Quaternions are an important tool to describe the orientation of a molecule. This paper considers the use of quaternions in matching two conformations of a molecule, in interpolating rotations, in performing statistics on orientational data, in the random ... More