Results for "Stefano Ettori"

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On the evolution of cooling cores in X-ray galaxy clustersFeb 02 2008(Abridged) To define a framework for the formation and evolution of the cooling cores in X-ray galaxy clusters, we study how the physical properties change as function of the cosmic time in the inner regions of a 4 keV and 8 keV galaxy cluster under the ... More
The relation between mass and concentration in X-ray galaxy clusters at high redshiftApr 07 2016Galaxy clusters are the most recent, gravitationally-bound products of the hierarchical mass accretion over cosmological scales. How the mass is concentrated is predicted to correlate with the total mass in the cluster's halo, with systems at higher mass ... More
CoMaLit-V. Mass forecasting with proxies. Method and application to weak lensing calibrated samplesMar 21 2016Mass measurements of astronomical objects are most wanted but still elusive. We need them to trace the formation and evolution of cosmic structure but we can get direct measurements only for a minority. This lack can be circumvented with a proxy and a ... More
CoMaLit-V. Mass forecasting with proxies. Method and application to weak lensing calibrated samplesMar 21 2016Mar 05 2017Mass measurements of astronomical objects are most wanted but still elusive. We need them to trace the formation and evolution of cosmic structure but we can get direct measurements only for a minority. This lack can be circumvented with a proxy and a ... More
CoMaLit-IV. Evolution and self-similarity of scaling relations with the galaxy cluster massFeb 18 2015May 01 2015The scaling of observable properties of galaxy clusters with mass evolves with time. Assessing the role of the evolution is crucial to study the formation and evolution of massive halos and to avoid biases in the calibration. We present a general method ... More
AGN Feedback in Galaxy Groups: the two interesting cases of AWM 4 and NGC 5044Sep 03 2009We present AGN feedback in the interesting cases of two groups: AWM 4 and NGC 5044. AWM 4 is characterized by a combination of properties which seems to defy the paradigm for AGN heating in cluster cores: a flat inner temperature profile indicative of ... More
Comparing Masses in Literature (CoMaLit)-I. Bias and scatter in weak lensing and X-ray mass estimates of clustersJul 29 2014May 01 2015The first building block to use galaxy clusters in astrophysics and cosmology is the accurate determination of their mass. Two of the most well regarded direct mass estimators are based on weak lensing (WL) determinations or X-ray analyses assuming hydrostatic ... More
Halo Concentrations and the Fundamental Plane of Galaxy ClustersDec 31 2018According to the standard cold dark matter (CDM) cosmology, the structure of dark halos including those of galaxy clusters reflects their mass accretion history. Older clusters tend to be more concentrated than younger clusters. Their structure, represented ... More
`Hyper Parameters' Approach to Joint Estimation: Applications to Cepheid-Calibrated Distances and X-Ray ClustersFeb 19 2002Nov 29 2002We use a generalised procedure for the combined likelihood analysis of different cosmological probes, the `Hyper-Parameters' method, that allows freedom in the relative weights of the raw measurements. We perform a joint analysis of the cepheid-calibrated ... More
Secular evolution of galaxies and galaxy clusters in decaying dark matter cosmologyMay 19 2009Sep 28 2009If the dark matter sector in the universe is composed by metastable particles, galaxies and galaxy clusters are expected to undergo significant secular evolution from high to low redshift. We show that the decay of dark matter, with a lifetime compatible ... More
X-ray morphological estimators for galaxy clustersNov 29 2012Jan 28 2013The classification of galaxy clusters according to their X-ray appearance is a powerful tool to discriminate between regular clusters (associated to relaxed objects) and disturbed ones (linked to dynamically active systems). The compilation of the two ... More
CoMaLit - II. The scaling relation between mass and Sunyaev-Zel'dovich signal for Planck selected galaxy clustersJul 29 2014May 01 2015We discuss the scaling relation between mass and integrated Compton parameter of a sample of galaxy clusters from the all-sky {\it Planck} Sunyaev-Zel'dovich catalogue. Masses were measured with either weak lensing, caustics techniques, or assuming hydrostatic ... More
Gravitational lensing detection of an extremely dense environment around a galaxy clusterJul 11 2018Galaxy clusters form at the highest density nodes of the cosmic web. The clustering of massive halos is enhanced relative to the general mass distribution and matter beyond the virial region is strongly correlated to the halo mass (halo bias). Clustering ... More
On the Discrepancy between Theoretical and X-Ray Concentration-Mass Relations for Galaxy ClustersJan 30 2013Sep 16 2013[Abridged] In the past 15 years, the concentration-mass relation has been investigated diffusely in theoretical studies. On the other hand, only recently has this relation been derived from X-ray observations. When that happened, the results caused a ... More
On the Iron content in rich nearby Clusters of GalaxiesOct 29 2003In this paper we study the iron content of a sample of 22 nearby hot clusters observed with BeppoSAX. We find that the global iron mass of clusters is tightly related to the cluster luminosity and that the relatively loose correlation between the iron ... More
The mass-concentration relation in lensing clusters: the role of statistical biases and selection effectsOct 16 2014Mar 17 2015The relation between mass and concentration of galaxy clusters traces their formation and evolution. Massive lensing clusters were observed to be over-concentrated and following a steep scaling in tension with predictions from the concordance $\Lambda$CDM ... More
Mass, shape and thermal properties of A1689 by a multi-wavelength X-ray, lensing and Sunyaev-Zel'dovich analysisOct 11 2012Knowledge of mass and concentration of galaxy clusters is crucial to understand their formation and evolution. Unbiased estimates require the understanding of the shape and orientation of the halo as well as its equilibrium status. We propose a novel ... More
Hydrodynamical simulations of galaxy clusters in dark energy cosmologies: II. c-M relationMay 14 2012Oct 17 2012We use hydrodynamical simulations of different dark energy cosmologies to investigate the concentration-mass (c-M) relation in galaxy clusters. In particular, we consider a reference \Lambda CDM model, two quintessence models with inverse power-law potentials ... More
Cosmology in 2D: the concentration-mass relation for galaxy clustersMay 10 2012Jul 30 2012The aim of this work is to perform a systematic study of the measures of the mass and concentration estimated by fitting the convergence profile of a large sample of mock galaxy cluster size lenses, created with the publicly available code MOKA. We found ... More
Self-similarity of temperature profiles in distant galaxy clusters: the quest for a Universal lawJun 28 2012Oct 22 2012We present the XMM-Newton temperature profiles of 12 bright clusters of galaxies at 0.4<z<0.9, with 5<kT<11 keV. The normalized temperature profiles (normalized by the mean temperature T500) are found to be generally self-similar. The sample was subdivided ... More
X-ray and strong lensing mass estimate of MS2137.3-2353Feb 24 2009We present new mass estimates of the galaxy cluster MS2137.3-2353, inferred from X-ray and strong lensing analyses. This cluster exhibits an outstanding strong lensing configuration and indicates a well-relaxed dynamical state, being most suitable for ... More
The X-ray/SZ view of the virial region. II. Gas mass fractionJan 03 2013Oct 07 2015Several recent studies used the hot gas fraction of galaxy clusters as a standard ruler to constrain dark energy, which provides competitive results compared to other techniques. This method, however, relies on the assumption that the baryon fraction ... More
The X-ray/SZ view of the virial region. I. Thermodynamic propertiesJan 03 2013Oct 07 2015We measure the thermodynamic properties of cluster outer regions to provide constraints on the processes that rule the formation of large scale structures. We derived the thermodynamic properties of the intracluster gas (temperature, entropy) by combining ... More
Baryon Census in Hydrodynamical Simulations of Galaxy ClustersSep 23 2012Feb 11 2013We carry out an analysis of a set of cosmological SPH hydrodynamical simulations of galaxy clusters and groups aimed at studying the total baryon budget in clusters, and how this budget is shared between the hot diffuse component and the stellar component. ... More
A Chandra - VLA Investigation of the X-ray Cavity System and Radio Mini-Halo in the Galaxy Cluster RBS 797Apr 27 2012We present a study of the cavity system in the galaxy cluster RBS 797 based on Chandra and VLA data. RBS 797 (z = 0.35), is one of the most distant galaxy clusters in which two pronounced X-ray cavities have been discovered. The Chandra data confirm the ... More
Excess entropy and energy feedback from within cluster cores up to r$_{200}$Feb 28 2017Aug 03 2017We estimate the "non-gravitational" entropy-injection profiles, $\Delta K$, and the resultant energy feedback profiles, $\Delta E$, of the intracluster medium for 17 clusters using their Planck SZ and ROSAT X-Ray observations, spanning a large radial ... More
A New Interpretation of the Mass-Temperature Relation and Mass Calibration of Galaxy Clusters Based on the Fundamental PlaneApr 13 2018Aug 14 2018Observations and numerical simulations have shown that the relation between the mass scaled with the critical density of the universe and the X-ray temperature of galaxy clusters is approximately represented by $M_\Delta \propto T_X^{3/2}$ (e.g. $\Delta=500$). ... More
Measurement of the dark matter velocity anisotropy in galaxy clustersAug 14 2008The internal dynamics of a dark matter structure may have the remarkable property that the local temperature in the structure depends on direction. This is parametrized by the velocity anisotropy beta which must be zero for relaxed collisional structures, ... More
Little evidence for non-gravitational energy feedback beyond $r_{500}$ - An end to ICM preheating?May 31 2016Non-gravitational feedback affects the nature of the intra-cluster medium (ICM). X-ray cooling of the ICM and in situ energy feedback from AGN's and SNe as well as preheating of the gas at epochs preceding the formation of clusters are proposed mechanisms ... More
The X-ray cavities, filaments and cold fronts in the core of the galaxy group NGC 5044Jul 22 2008Oct 22 2008We present a two-dimensional analysis of the bright nearby galaxy group NGC 5044 using the currently available Chandra and XMM data. In the inner 10 kpc a pair of cavities are evident together with a set of bright X-ray filaments. If the cavities are ... More
Hydrodynamical simulations of galaxy clusters in dark energy cosmologies: I. general propertiesAug 31 2010Mar 23 2012We investigate the influence of dark energy on structure formation, within five different cosmological models, namely a concordance $\Lambda$CDM model, two models with dynamical dark energy, viewed as a quintessence scalar field (using a RP and a SUGRA ... More
Searching for Cool Core Clusters at High redshiftFeb 11 2008We investigate the detection of Cool Cores (CCs) in the distant galaxy cluster population, with the purpose of measuring the CC fraction out to redshift 0.7 < z < 1.4. Using a sample of nearby clusters spanning a wide range of morphologies, we define ... More
Mass and Concentration estimates from Weak and Strong Gravitational Lensing: a Systematic StudyNov 05 2013Feb 12 2014We study how well halo properties of galaxy clusters, like mass and concentration, are recovered using lensing data. In order to generate a large sample of systems at different redshifts we use the code MOKA. We measure halo mass and concentration using ... More
The Three-Dimensional Shapes of Galaxy ClustersOct 10 2012While clusters of galaxies are considered one of the most important cosmological probes, the standard spherical modelling of the dark matter and the intracluster medium is only a rough approximation. Indeed, it is well established both theoretically and ... More
PSZ2LenS. Weak lensing analysis of the Planck clusters in the CFHTLenS and in the RCSLenSMar 20 2017Sep 04 2017The possibly unbiased selection process in surveys of the Sunyaev Zel'dovich effect can unveil new populations of galaxy clusters. We performed a weak lensing analysis of the PSZ2LenS sample, i.e. the PSZ2 galaxy clusters detected by the Planck mission ... More
Spatial Distribution of Metals in the ICM: Evolution of the Iron Excess in Relaxed Galaxy ClustersAug 21 2018We investigate the spatial distribution of iron in the intra-cluster medium in a selected sample of 41 relaxed clusters in the redshift range $0.05 < z < 1.03$ using {\sl Chandra} archival data. We compute the azimuthally-averaged, deprojected $Z_{\rm ... More
An XMM-Newton spatially-resolved study of metal abundance evolution in distant galaxy clustersNov 18 2011Dec 02 2011We present an XMM-Newton analysis of the X-ray spectra of 39 clusters of galaxies at 0.4<z<1.4, covering a temperature range of 1.5<=kT<=11 keV. We performed a spatially resolved spectral analysis to study how the abundance evolves with redshift not only ... More
Little evidence for entropy and energy excess beyond $r_{500}$ - An end to ICM preheating?May 31 2016Oct 27 2016Non-gravitational feedback affects the nature of the intra-cluster medium (ICM). X-ray cooling of the ICM and in situ energy feedback from AGN's and SNe as well as {\it preheating} of the gas at epochs preceding the formation of clusters are proposed ... More
The Physics of Galaxy Cluster OutskirtsOct 01 2018Jan 04 2019As the largest virialized structures in the universe, galaxy clusters continue to grow and accrete matter from the cosmic web. Due to the low gas density in the outskirts of clusters, measurements are very challenging, requiring extremely sensitive telescopes ... More
CLUMP-3D. Testing $Λ$CDM with galaxy cluster shapesApr 02 2018May 21 2018The $\Lambda$CDM model of structure formation makes strong predictions on concentration and shape of DM (dark matter) halos, which are determined by mass accretion processes. Comparison between predicted shapes and observations provides a geometric test ... More
The inverse iron-bias in action in Abell 2028Sep 25 2009Recent work based on a global measurement of the ICM properties find evidence for an increase of the iron abundance in galaxy clusters with temperature around 2-4 keV. We have undertaken a study of the metal distribution in nearby clusters in this temperature ... More
Outskirts of Galaxy ClustersMar 13 2013Until recently, only about 10% of the total intracluster gas volume had been studied with high accuracy, leaving a vast region essentially unexplored. This is now changing and a wide area of hot gas physics and chemistry awaits discovery in galaxy cluster ... More
CLUMP-3D. Three dimensional lensing and multi-probe analysis of MACS J1206.2-0847, a remarkably regular clusterFeb 02 2017Multi-wavelength techniques can probe the distribution and the physical properties of baryons and dark matter in galaxy clusters from the inner regions out to the peripheries. We present a full three-dimensional analysis combining strong and weak lensing, ... More
CLUMP-3D: Three-dimensional Shape and Structure of 20 CLASH Galaxy Clusters from Combined Weak and Strong LensingApr 02 2018May 11 2018We perform a three-dimensional triaxial analysis of 16 X-ray regular and 4 high-magnification galaxy clusters selected from the CLASH survey by combining two-dimensional weak-lensing and central strong-lensing constraints. In a Bayesian framework, we ... More
Probing Macro-Scale Gas Motions and Turbulence in Diffuse Cosmic PlasmasMar 11 2019Mar 14 2019Clusters of galaxies, the largest collapsed structures in the Universe, are located at the intersection of extended filaments of baryons and dark matter. Cosmological accretion onto clusters through large scale filaments adds material at cluster outskirts. ... More
Quantum Teleportation with Continuous Variables: a surveyApr 05 2006Oct 12 2006Very recently we have witnessed a new development of quantum information, the so-called continuous variable (CV) quantum information theory. Such a further development has been mainly due to the experimental and theoretical advantages offered by CV systems, ... More
A note on the existence of $L^2$ valued solutions for a hyperbolic system with boundary conditionsNov 13 2018Feb 08 2019We prove existence of $L^2$-weak solutions of a quasilinear wave equation with boundary conditions.This is done using a vanishing viscosity approximation with mixed Dirichlet-Neumann boundary conditions. In this setting we obtain a uniform a priori estimate ... More
Hydrodynamic Limit for an Anharmonic Chain under Boundary TensionFeb 06 2018Jun 11 2018We study the hydrodynamic limit for the isothermal dynamics of an anharmonic chain under hyperbolic space-time scaling under varying tension. The temperature is kept constant by a contact with a heat bath, realised via a stochastic momentum-preserving ... More
On a quadratic functional for scalar conservation lawsNov 12 2013We prove a quadratic interaction estimate for approximate solutions to scalar conservation laws obtained by the wavefront tracking approximation or the Glimm scheme. This quadratic estimate has been used in the literature to prove the convergence rate ... More
On the existence of $L^2$-valued thermodynamic entropy solutions for a hyperbolic system with boundary conditionsNov 13 2018May 13 2019We prove existence of $L^2$-weak solutions of a quasilinear wave equation with boundary conditions. This describes the isothermal evolution of a one dimensional non-linear elastic material, attached to a fixed point on one side and subject to a force ... More
The SKA view of cool-core clusters: evolution of radio mini-halos and AGN feedbackDec 17 2014In about 70% of the population of relaxed, cool-core galaxy clusters, the brightest cluster galaxy (BCG) is radio loud, showing non-thermal radio jets and lobes ejected by the central active galactic nucleus (AGN). In recent years such relativistic plasma ... More
Three-dimensional Multi-probe Analysis of the Galaxy Cluster A1689Mar 04 2015May 14 2015We perform a 3D multi-probe analysis of the rich galaxy cluster A1689 by combining improved weak-lensing data from new BVRi'z' Subaru/Suprime-Cam observations with strong-lensing, X-ray, and Sunyaev-Zel'dovich effect (SZE) data sets. We reconstruct the ... More
The Morphologies and Alignments of Gas, Mass, and the Central Galaxies of CLASH Clusters of GalaxiesJan 19 2016Morphology is often used to infer the state of relaxation of galaxy clusters. The regularity, symmetry, and degree to which a cluster is centrally concentrated inform quantitative measures of cluster morphology. The Cluster Lensing and Supernova survey ... More
X-Ray morphological analysis of the Planck ESZ clustersAug 08 2017X-ray observations show that galaxy clusters have a very large range of morphologies. The most disturbed systems which are good to study how clusters form and grow and to test physical models, may potentially complicate cosmological studies because the ... More
The Future Landscape of High-Redshift Galaxy Cluster ScienceMar 13 2019Modern galaxy cluster science is a multi-wavelength endeavor with cornerstones provided by X-ray, optical/IR, mm, and radio measurements. In combination, these observations enable the construction of large, clean, complete cluster catalogs, and provide ... More
Performance of the Pierre Auger Fluorescence Detector and Analysis of well recontructed eventsAug 25 2003The Pierre Auger Observatory is designed to elucidate the origin and nature of Ultra High Energy Cosmic Rays using a hybrid detection technique. A first run of data taking with a prototype version of both detectors (the so called Engineering Array) took ... More
Performance of the CMS Tracker Optical Links and Future Upgrade Using Bandwidth Efficient Digital ModulationApr 30 2010(Abridged version) The CMS experiment at the LHC will begin operation in 2007. The CMS Tracker sub-detector, comprises ~10 million detector channels read out by ~40 000 analog optical links. The optoelectronic components have been designed to meet the ... More
Stability and Instability of Extreme Reissner-Nordström Black Hole Spacetimes for Linear Scalar Perturbations IIOct 10 2011This paper contains the second part of a two-part series on the stability and instability of extreme Reissner-Nordstrom spacetimes for linear scalar perturbations. We continue our study of solutions to the linear wave equation on a suitable globally hyperbolic ... More
Stability and Instability of Extreme Reissner-Nordström Black Hole Spacetimes for Linear Scalar Perturbations IOct 10 2011We study the problem of stability and instability of extreme Reissner-Nordstrom spacetimes for linear scalar perturbations. Specifically, we consider solutions to the linear wave equation on a suitable globally hyperbolic subset of such a spacetime, arising ... More
The Wave Equation on Extreme Reissner-Nordström Black Hole Spacetimes: Stability and Instability ResultsJun 02 2010Oct 10 2011We consider solutions to the linear wave equation on a suitable globally hyperbolic subset of an extreme Reissner-Nordstrom spacetime, arising from regular initial data prescribed on a Cauchy hypersurface crossing the future event horizon. We obtain boundedness, ... More
Nonlinear instability of scalar fields on extremal black holesApr 16 2013We prove a new type of finite time blow-up for a class of semilinear wave equations on extremal black holes. The initial data can be taken to be arbitrarily close to the trivial data. The first singularity occurs along the (degenerate) future event horizon. ... More
On Lasso-type estimation for dynamical systems with small noiseDec 27 2009Aug 20 2016We consider a dynamical system with small noise for which the drift is parametrized by a finite dimensional parameter. For this model we consider minimum distance estimation from continuous time observations under L-p penalty imposed on the parameters ... More
Phenomenology of TMDsDec 04 2014We present a review of current Transverse Momentum Dependent (TMD) phenomenology focusing our attention on the unpolarized TMD parton distribution function and the Sivers function. The paper introduces and comments about the new Collins-Soper-Sterman ... More
Colourful FKS subtractionJun 01 2011I formulate in a colour-friendly way the FKS method for the computation of QCD cross sections at the next-to-leading order accuracy. This is achieved through the definition of subtraction terms for squared matrix elements, constructed with single colour-dressed ... More
An alternative approach to b->sγin the unconstrained MSSMApr 15 2002The gluino contributions to the $C'_{7,8}$ Wilson coefficients for b->s\gamma are calculated within the unconstrained MSSM. New stringent bounds on the \dRLbs and \dRRbs mass insertion parameters are obtained in the limit in which the SM and SUSY contributions ... More
Breaking entanglement-breaking by classical correlationsJul 22 2013The inevitable interaction between quantum systems and environment induces effects of decoherence which may be so strong as to destroy any initial entanglement between the systems, a phenomenon known as "entanglement breaking". Here we show the simplest ... More
Progress in perturbative QCDJun 17 1997Jun 25 1997We briefly summarize some recent theoretical developments in perturbative QCD, emphasizing new ideas which have led to widening the domain of applicability of perturbation theory. In particular, it is now possible to calculate efficiently processes with ... More
Violation of the Bjorken Sum Rule in QCDNov 07 1992Nov 17 1992We show that the Bjorken sum rule for the first moment of the polarized nucleon structure function $g_1$ is not necessarily satisfied in QCD if the axial anomaly is taken into account. We argue that nonperturbative QCD effects should lead to a violation ... More
Spin in quantum field theoryJul 29 2005Aug 29 2006I introduce spin in field theory by emphasizing the close connection between quantum field theory and quantum mechanics. First, I show that the spin-statistics connection can be derived in quantum mechanics without relativity or field theory. Then, I ... More
Relativistic Quantum Theory with Fractional Spin and StatisticsJul 07 1993These lectures discuss the formulation of quantum mechanics with fractional spin and statistics in 2+1 dimensions in a relativistic setting, emphasizing the path-integral approach. The non-relativistic theory is reviewed from a path-integral viewpoint. ... More
Accelerating the pace of discovery by changing the peer review algorithmNov 02 2009The number of scientific publications is constantly rising, increasing the strain on the review process. The number of submissions is actually higher, as each manuscript is often reviewed several times before publication. To face the deluge of submissions, ... More
Some results on ideal impacts of billiard ballsNov 23 2007We analyze the impact of two equal billiard balls in three ideal situations: when the balls freely slide on the plane of the billiard, when they roll without sliding and when one of them freely slides and the other rolls. In all the cases we suppose that ... More
Holographic Grid Cloud, a futurable high storage technology for the next generation astronomical facilitiesDec 28 2011Jan 09 2012In the immediate future holographic technology will be available to store a very large amount of data in HVD (Holographic Versatile Disk) devices. This technology make extensive use of the WORM (Write-Once-Read-Many) paradigm: this means that such devices ... More
Markovian feedback to control continuous variable entanglementMar 26 2005Apr 18 2005We present a model to realize quantum feedback control of continuous variable entanglement. It consists of two interacting bosonic modes subject to amplitude damping and achieving entangled Gaussian steady state. The possibility to greatly improve the ... More
Defect and evaluationsApr 16 1996Let $S$ be a generic submanifold of $C^N$ of real codimension m. In this work we continue the study, carried over by various authors, of the set of analytic discs attached to S. Let $M$ be the set of analytic discs attached to $S.$ Given $q \in S$ let ... More
TOTEM: The experiment to measure the total proton-proton cross section at LHCDec 21 2006The current large uncertainty on the extrapolation of the proton-proton total cross section at the LHC energy will be resolved by the precise measurement by the TOTEM experiment. Its accurate studies on the basic properties of proton-proton collisions ... More
Beyond the Standard Model at Belle: B to K*l+l- and search for leptonic B decaysMay 29 2006We report the first measurement of the forward-backward asymmetry and the ratios of Wilson coefficients A_9/A_7 and A_10/A_7 in B to K*l+l-, obtained using 386M BBbar pairs that were collected at the Y(4S) resonance with the Belle detector at the KEKB ... More
The Hardy-Littlewood Lemma and the estimate of the $\dib$-Neumann problem in a general normAug 10 2012We prove a generalized Hardy-Littlewood lemma on a non-smooth domain in "$f$-norm" and give an application to a corresponding estimate for the $\dib$-Neumann problem by means of suitable weights.
Supersymmetric transparent optical intersectionsNov 26 2014Jan 09 2015Supersymmetric (SUSY) optical structures provide a versatile platform to manipulate the scattering and localization properties of light, with potential applications to mode conversion, spatial multiplexing and invisible devices. Here we show that SUSY ... More
Anti-Newtonian dynamics and self-induced Bloch oscillations of correlated particlesSep 01 2014We predict that two correlated particles hopping on a one-dimensional Hubbard lattice can show transient self-acceleration and self-induced Bloch oscillations as a result of anti-Newtonian dynamics. Self-propulsion occurs for two particles with opposite ... More
Invisible surface defects in a tight-binding latticeJun 24 2014Surface Tamm states arise in one-dimensional lattices from some defects at the lattice edge and their energy generally falls in a gap of the crystal. The defects at the surface change rather generally the phase of propagative Bloch waves scattered off ... More
Exceptional points and Bloch oscillations in non-Hermitian lattices with unidirectional hoppingApr 14 2014The spectral and transport properties of a non-Hermitian tight-binding lattice with unidirectional hopping are theoretically investigated in three different geometrical settings. It is shown that, while for the infinitely-extended (open) and for the ring ... More
Zak phase of photons in optical waveguide latticesOct 18 2013Zak phase, i.e. the Berry phase acquired during an adiabatic motion of a Bloch particle across the Brillouin zone, provides a measure of the topological invariant of Bloch bands in one-dimensional crystalline potentials. Here a photonic structure, based ... More
Coherent perfect absorption in a homogeneously-broadened two-level mediumNov 15 2011In recent works, it has been shown rather generally that the time-reversed process of lasing at threshold realizes a coherent perfect absorber (CPA). In a CPA, a lossy medium in an optical cavity with a speci?c degree of dissipation, equal in modulus ... More
Photonic Bloch oscillations of correlated particlesNov 15 2011A photonic realization of Bloch oscillations (BOs) of two correlated electrons that move on a one-dimensional periodic lattice, based on spatial light transport in a square waveguide array with a defect line, is theoretically proposed. The signature of ... More
Airy beams from a microchip laserFeb 02 2011It is theoretically shown that an end-pumped microchip laser formed by a thin laser crystal with plane-plane but slightly tilted facets can emit, under appropriate pumping conditions and near a crystal edge, a truncated self-accelerating Airy output beam. ... More
Dynamical trapping of light in modulated waveguide latticesFeb 02 2011A discrete analogue of the dynamical (Kapitza) trapping effect, known for classical and quantum particles in rapidly oscillating potentials, is proposed for light waves in modulated graded-index waveguide lattices. As in the non-modulated waveguide lattice ... More
Photonic realization of the relativistic Dirac oscillatorSep 01 2010A photonic realization of the Dirac oscillator (DO), i.e. of the relativistic extension of the quantum harmonic oscillator, is proposed for light propagation in fiber Bragg gratings. Transmission spectra clearly show the existence of electron and positron ... More
Phase transitions in Wick-rotated $\mathcal{PT}$-symmetric opticsOct 08 2014May 15 2015$\mathcal{PT}$-symmetric models with a Wick rotation of time ($ t \rightarrow \pm i t$) show spectral phase transitions that are similar to those of dissipative systems driven out of equilibrium. Optics can provide an accessible test bed to explore spectral ... More
Adiabatic quantum state transfer in tight-binding chains using periodic driving fieldsAug 08 2014A method for high-fidelity coherent adiabatic transport in a zig-zag tight-binding chain, based on application of two external periodic driving fields, is theoretically proposed. The method turns out to be robust against imperfections and disorder of ... More
Aharonov-Bohm photonic cages in waveguide and coupled resonator lattices by synthetic magnetic fieldsJul 13 2014Sep 27 2014We suggest a method for trapping photons in quasi one-dimensional waveguide or coupled-resonator lattices, which is based on an optical analogue of the Aharonov-Bohm cages for charged particles. Light trapping results from a destructive interference of ... More
Effective magnetic fields for photons in waveguide and coupled resonator latticesOct 18 2013A method to realize effective magnetic fields for photons in square lattices of coupled optical waveguides or resonators is suggested, which is inspired by an optical analogue of photon-assisted tunneling of atom optics. It is shown that an artificial ... More
Optical realization of two-boson tunneling dynamicsNov 15 2011An optical realization of the tunneling dynamics of two interacting bosons in a double-well potential, based on light transport in a four-core microstructured fiber, is proposed. The optical setting enables to visualize in a purely classical system the ... More
Jaynes Cummings Photonic SuperlatticesNov 15 2011A classical realization of the Jaynes-Cummings (JC) model, describing the interaction of a two-level atom with a quantized cavity mode, is proposed based on light transport in engineered waveguide superlattices. The optical setting enables to visualize ... More
On systems with finite ergodic degreeAug 04 2003In this paper we study the ergodic theory of a class of symbolic dynamical systems $(\O, T, \mu)$ where $T:{\O}\to \O$ the left shift transformation on $\O=\prod_0^\infty\{0,1\}$ and $\mu$ is a $\s$-finite $T$-invariant measure having the property that ... More
Physics of Heavy Flavour at CDFJun 24 2005Results on physics of heavy flavour at CDF are reported. Selected measurements of Branching Ratios and CP asymmetry in $B^0$ and $B_s^0$, lifetime difference of $B^0_s$ CP eigenstates and a precise measurement of the $B_c$ mass are presented.
A general method for the determination of duration of solar cycle maximaOct 10 2013The use of different solar activity indices like sunspot numbers, sunspot areas, flare index, magnetic fields, etc., allows us to investigate the time evolution of some specific features of the solar activity and the underlying dynamo mechanism. One of ... More
Solar Cycle 24: is the peak coming?Sep 27 2012Sep 28 2012Solar cycle activity forecasting, mainly its magnitude and timing, is an essential issue for numerous scientific and technological applications: in fact, during an active solar period, many strong eruptions occur on the Sun with increasing frequency, ... More
On the correlation between air temperature and the core Earth processes: Further investigations using a continuous wavelet analysisMar 25 2011In a recent article by Dickey, J. O., Marcus, S.L. and O. de Viron, 2011, the authors show evidences for correlations in the multi-decadal variability of Earth's rotation rate [i.e., length of day (LOD)], the angular momentum of the core (CAM), and natural ... More
Auto-Correlation Functions and Solar Cycle PredictabilityOct 05 2000Starting from the traditional definition of auto-correlation function we can introduce a new quantity, based on the wavelet formalism, called local wavelet auto-correlation function, which contains more information about the correlation properties on ... More