Results for "C. Petrillo"

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Disentangling time-focusing from beam divergence: a novel approach for high-flux thermal neutron spectroscopy at continuous and long-pulse sourcesApr 12 2019We present the concept of a novel time-focusing technique for neutron spectrometers, which allows to disentangle time-focusing from beam divergence. The core of this approach is a double rotating-crystal monochromator that can be used to extract a larger ... More
Low emittance pion beams generation from bright photons and relativistic protonsJul 23 2015Aug 07 2015Present availability of high brilliance photon beams as those produced by X-ray Free Electron Lasers in combination with intense TeV proton beams typical of the Large Hadron Collider makes it possible to conceive the generation of pion beams via photo-production ... More
Real-time observation of the isothermal crystallization kinetics in a deeply supercooled liquidNov 11 2016Below the melting temperature $T_m$ crystals are the stable phase of typical elemental or molecular systems. However, cooling down a liquid below $T_m$, crystallization is anything but inevitable. The liquid can be supercooled, eventually forming a glass ... More
Temperature dependence of the surface plasmon resonance in small electron gas fragments, self consistent field approximationApr 27 2017The temperature dependence of the surface plasmon resonance in small metal spheres is calculated using an electron gas model within the Random Phase Approximation. The calculation is mainly devoted to the study of spheres with diameters up to at least ... More
Comment to the paper: 'Seeded quantum FEL at 478 keV' AIP Conf. Proc. 'Light at Extreme Intensities' 1462 173-176 (2012)'Dec 19 2012We criticize the thesis exposed the paper 'Seeded quantum FEL at 478 keV' AIP Conf. Proc. 'Light at Extreme Intensities,' 1462 173-176 (2012), which presents the possibility of producing gamma rays at 478 KeV by means of a seeded quantum FEL driven by ... More
Pressure induced magnetic phase separation in La$_{0.75}$Ca$_{0.25}$MnO$_{3}$ manganiteDec 08 2011The pressure dependence of the Curie temperature T$_{C}(P)$ in La$_{0.75}$Ca$_{0.25}$MnO$_{3}$ was determined by neutron diffraction up to 8 GPa, and compared with the metallization temperature T$_{IM}(P)$ \cite{irprl}. The behavior of the two temperatures ... More
Electron beam transfer line design for plasma driven Free Electron LasersMar 01 2018Plasma driven particle accelerators represent the future of compact accelerating machines and Free Electron Lasers are going to benefit from these new technologies. One of the main issue of this new approach to FEL machines is the design of the transfer ... More
Identifying Galaxy Mergers in Observations and Simulations with Deep LearningFeb 27 2019Mergers are an important aspect of galaxy formation and evolution. We aim to test whether deep learning techniques can be used to reproduce visual classification of observations, physical classification of simulations and highlight any differences between ... More
Identifying Galaxy Mergers in Observations and Simulations with Deep LearningFeb 27 2019May 10 2019Mergers are an important aspect of galaxy formation and evolution. We aim to test whether deep learning techniques can be used to reproduce visual classification of observations, physical classification of simulations and highlight any differences between ... More
Spontaneous and Stimulated Star Formation in GalaxiesJan 09 2008We present recent results from several on-going studies: The first addresses the question of gas-density thresholds for star formation, as probed by the outer disks of normal nearby galaxies. The second concerns the observational evidence for the existence ... More
Identifying Galaxy Mergers in Observations and Simulations with Deep LearningFeb 27 2019Mar 01 2019Mergers are an important aspect of galaxy formation and evolution. We aim to test whether deep learning techniques can be used to reproduce visual classification of observations, physical classification of simulations and highlight any differences between ... More
Ergodicity breaking in strong and network-forming glassy systemSep 24 2008The temperature dependence of the non-ergodicity factor of vitreous GeO$_2$, $f_{q}(T)$, as deduced from elastic and quasi-elastic neutron scattering experiments, is analyzed. The data are collected in a wide range of temperatures from the glassy phase, ... More
Summary of the Second Workshop on Liquid Argon Time Projection Chamber Research and Development in the United StatesApr 21 2015Apr 23 2015The second workshop to discuss the development of liquid argon time projection chambers (LArTPCs) in the United States was held at Fermilab on July 8-9, 2014. The workshop was organized under the auspices of the Coordinating Panel for Advanced Detectors, ... More
Role of charge doping and lattice distortions in codoped Mg_{1-x}(AlLi)_{x}B_2 compoundsJun 07 2005Jan 31 2006We prepared a series of Mg_{1-x}(AlLi)_{x}B_2 samples with 0≤x≤0.45 in order to compensate with Li the electron doping induced by Al. Structural characterization by means of neutron and X-ray diffraction confirms that Li enters the MgB2 structure ... More
Finding Strong Gravitational Lenses in the Kilo Degree Survey with Convolutional Neural NetworksFeb 24 2017Aug 23 2017The volume of data that will be produced by new-generation surveys requires automatic classification methods to select and analyze sources. Indeed, this is the case for the search for strong gravitational lenses, where the population of the detectable ... More
RF injector design studies for the trailing witness bunch for a plasma-based user facilityJan 09 2018Jan 16 2018The interest in plasma-based accelerators as drivers of user facilities is growing worldwide thanks to its compactness and reduced costs. In this context the EuPRAXIA collaboration is preparing a conceptual design report for a multi-GeV plasma-based accelerator ... More
Plasma boosted electron beams for driving Free Electron LasersFeb 19 2018In this paper, we report results of simulations, in the framework of both EuPRAXIA \cite{Walk2017} and EuPRAXIA@SPARC\_LAB \cite{Ferr2017} projects, aimed at delivering a high brightness electron bunch for driving a Free Electron Laser (FEL) by employing ... More
A muon source based on plasma acceleratorsNov 16 2017Nov 18 2017The conceptual design of a compact source of GeV-class muons is presented, based on a plasma based electron-gamma collider. Evaluations of muon flux, spectra and brilliance are presented, carried out with ad-hoc montecarlo simulations of the electron-gamma ... More
EuPRAXIA@SPARC_LAB: the high-brightness RF photo-injector layout proposalFeb 25 2018At EuPRAXIA@SPARC_LAB, the unique combination of an advanced high-brightness RF injector and a plasma-based accelerator will drive a new multi-disciplinary user-facility. The facility, that is currently under study at INFN-LNF Laboratories (Frascati, ... More
Laser Heater and seeded Free Electron LaserOct 24 2014Feb 16 2015In this paper we consider the effect of laser heater on a seeded Free Electron Laser. We develop a model embedding the effect of the energy modulation induced by the heater with those due to the seeding. The present analysis is compatible with the experimental ... More
Compact object coalescence rate estimation from short gamma-ray burst observationsFeb 03 2012Apr 09 2013Recent observational and theoretical results suggest that Short-duration Gamma-Ray Bursts (SGRBs) are originated by the merger of compact binary systems of two neutron stars or a neutron star and a black hole. The observation of SGRBs with known redshifts ... More
Asymptotic non-MarkovianitySep 04 2016We investigate the asymptotic dynamics of exact quantum Brownian motion. We find that non-Markovianity can persist in the long-time limit, and that in general the asymptotic behaviour depends strongly on the system-environment coupling and the spectral ... More
Atlas and Catalog of Collisional Ring GalaxiesFeb 26 2009We present a catalog and imaging atlas of classical (collisional) RING galaxies distilled from the Arp-Madore Atlas of Southern Peculiar Galaxies and Associations and supplemented with other known RING galaxies from the published literature. The catalog ... More
D-optimal design of b-values for accurate intra-voxel incoherent motion imagingOct 03 2016The aim of this paper is to optimally design the set of b-values for diffusion weighted MRI with the aim of accurate estimation of intra- voxel incoherent motion (IVIM) parameters (f perfusion fraction, Ds slow diffusion, Df fast diffusion) according ... More
Serverless architecture efficiency: an exploratory studyJan 13 2019Cloud service provider propose services to insensitive customers to use their platform. Different services can achieve the same result at different cost. In this paper, we study the efficiency of a serverless architecture for running highly parallelizable ... More
Gamma Factory at CERN - novel research tools made of lightMar 21 2019We discuss the possibility of creating novel research tools by producing and storing highly relativistic beams of highly ionised atoms in the CERN accelerator complex, and by exciting their atomic degrees of freedom with lasers to produce high-energy ... More
EUPRAXIA@SPARC_LAB: Beam Dynamics studies for the X-band LinacJan 30 2018In the framework of the Eupraxia Design Study an advanced accelerator facility EUPRAXIA@SPARC_LAB has been proposed to be realized at Frascati (Italy) Laboratories of INFN. Two advanced acceleration schemes will be applied, namely an ultimate high gradient ... More
Apparent superluminal advancement of a single photon far beyond its coherence lengthMay 09 2008Apr 16 2009We present experimental results relative to superluminal propagation based on a single photon traversing an optical system, called 4f-system, which acts singularly on the photon's spectral component phases. A single photon is created by a CW laser light ... More
Fault heterogeneity and the connection between aftershocks and afterslipDec 14 2018Whether aftershocks originate directly from the mainshock and surrounding stress environment or from afterslip dynamics is crucial to the understanding of the nature of aftershocks. We build on a classical description of the fault and creeping regions ... More
Software Architecture Metrics: a literature reviewJan 25 2019In Software Engineering, early detection of architectural issues is key. It helps mitigate the risk of poor performance, and lowers the cost of repairing these issues. Metrics give a quick overview of the project which helps designers with the detection ... More
Micronucleus induction by 915 MHz Radiofrequency Radiation in Vicia faba root tipsSep 04 2014The mutagenic effect of radiofrequency electromagnetic field (RF-EMF) is evaluated by the micronucleus (MN) test in secondary roots of Vicia faba seedlings. Root exposures were carried out with 915 MHz continuous wave (CW) radiation for 72h, at power ... More
A quality model for evaluating and choosing a stream processing framework architectureJan 25 2019Today, we have to deal with many data (Big data) and we need to make decisions by choosing an architectural framework to analyze these data coming from different area. Due to this, it become problematic when we want to process these data, and even more, ... More
Using HTML5 to Prevent Detection of Drive-by-Download Web MalwareJul 13 2015The web is experiencing an explosive growth in the last years. New technologies are introduced at a very fast-pace with the aim of narrowing the gap between web-based applications and traditional desktop applications. The results are web applications ... More
Problems and Solutions of Continuous Deployment: A Systematic ReviewDec 21 2018Context: The software industry needs to adapt itself to a rapidly changing market. Continuous practices (Continuous Integration, Continuous Delivery and Continuous Deployment), commonly found in Agile development processes, it is possible to deliver new ... More
LinKS: Discovering galaxy-scale strong lenses in the Kilo-Degree Survey using Convolutional Neural NetworksDec 07 2018Jan 16 2019We present a new sample of galaxy-scale strong gravitational-lens candidates, selected from 904 square degrees of Data Release 4 of the Kilo-Degree Survey (KiDS), i.e., the "Lenses in the Kilo-Degree Survey" (LinKS) sample. We apply two Convolutional ... More
The first sample of spectroscopically confirmed ultra-compact massive galaxies in the Kilo Degree SurveyJun 04 2018Sep 18 2018We present results from an ongoing investigation using the Kilo Degree Survey (KiDS) on the VLT Survey Telescope (VST) to provide a census of ultra-compact massive galaxies (UCMGs), defined as galaxies with stellar masses $M_{\rm \star} > 8 \times 10^{10} ... More
Quantum coherence of Gaussian statesSep 04 2016We introduce a geometric quantification of quantum coherence in single-mode Gaussian states and we investigate the behavior of distance measures as functions of different physical parameters. In the case of squeezed thermal states, we observe that re-quantization ... More
Analyzing Big Datasets of Genomic Sequences: Fast and Scalable Collection of k-mer StatisticsJul 04 2018Distributed approaches based on the map-reduce programming paradigm have started to be proposed in the bioinformatics domain, due to the large amount of data produced by the next-generation sequencing techniques. However, the use of map-reduce and related ... More
Deep Learning for Galaxy Mergers in the Galaxy Main SequenceJan 22 2019Starburst galaxies are often found to be the result of galaxy mergers. As a result, galaxy mergers are often believed to lie above the galaxy main sequence: the tight correlation between stellar mass and star formation rate. Here, we aim to test this ... More
SPH Simulations of Regular and Irregular Waves and their Comparison with Experimental DataNov 10 2009This paper presents the Smoothed particle hydrodynamics (SPH) model to examine the propagation of a regular and irregular waves. The SPH method is a grid-less Lagrangian approach which is capable of good accuracy in tracking large deformations of a free ... More
Swarm Debugging: the Collective Intelligence on Interactive DebuggingFeb 10 2019One of the most important tasks in software maintenance is debugging. To start an interactive debugging session, developers usually set breakpoints in an integrated development environment and navigate through different paths in their debuggers. We started ... More
High energy Free Electron Laser for nuclear applicationsApr 02 2018The capability of Free-Electron Lasers to generate photon beams with record performances in the domain of MeV-class photon energy for nuclear photonics applications is here analyzed. We discuss possible nuclear FEL working points. Some typical situations ... More
Water in a Polymeric Electrolyte Membrane: Sorption/Desorption and Freezing phenomenaMay 02 2013Dec 17 2013Nafion is a perfluorosulfonated polymer, widely used in Proton Exchange Membrane Fuel Cells. This polymer adopts a complex structural organisation resulting from the microsegregation between hydrophobic backbones and hydrophilic sulfonic acid groups. ... More
Improving performance of inverse Compton sources through laser chirpingFeb 12 2019We present a new paradigm for computation of radiation spectra in the non-linear regime of operation of inverse Compton sources characterized by high laser intensities. The resulting simulations show an unprecedented level of agreement with the experiments. ... More
K2-140b and K2-180b - Characterization of a hot Jupiter and a mini-Neptune from the K2 missionOct 10 2018Oct 11 2018We report the independent discovery and characterization of two K2 planets: K2-180b, a mini-Neptune-size planet in an 8.9-day orbit transiting a V = 12.6 mag, metal-poor ([Fe/H] =$-0.65\pm0.10$) K2V star in K2 campaign 5; K2-140b, a transiting hot Jupiter ... More
The Herschel-ATLAS: a sample of 500μm-selected lensed galaxies over 600 square degreesNov 12 2016We present a sample of 80 candidate strongly lensed galaxies with flux density above 100mJy at 500{\mu}m extracted from the Herschel Astrophysical Terahertz Large Area Survey (H-ATLAS), over an area of 600 square degrees. Available imaging and spectroscopic ... More
Deep Saturated Free Electron Laser Oscillators and Frozen SpikesJan 27 2016We analyze the behavior of Free Electron Laser (FEL) oscillators operating in the deep saturated regime and point out the formation of sub-peaks of the optical pulse. They are very stable configurations, having a width corresponding to a coherence length. ... More
Revisiting the bulge-halo conspiracy II: Towards explaining its puzzling dependence on redshiftNov 21 2017We carry out a systematic investigation of the total mass density profile of massive (Mstar~3e11 Msun) early-type galaxies and its dependence on redshift, specifically in the range 0<z<1. We start from a large sample of SDSS early-type galaxies with stellar ... More
The Strong Gravitational Lens Finding ChallengeFeb 10 2018Mar 20 2019Large scale imaging surveys will increase the number of galaxy-scale strong lensing candidates by maybe three orders of magnitudes beyond the number known today. Finding these rare objects will require picking them out of at least tens of millions of ... More
Plasma acceleration limitations due to betatron radiationFeb 09 2018High energy spread caused by the longitudinal size of the beam is well known in wake-field acceleration. Usually this issue can be solved with beam loading effect that allows to keep accelerating field nearly constant, along the whole duration of the ... More
Pathway to a Compact SASE FEL DeviceMay 29 2015Newly developed high peak power lasers have opened the possibilities of driving coherent light sources operating with laser plasma accelerated beams and wave undulators. We speculate on the combination of these two concepts and show that the merging of ... More
Precise measurement of the top quark mass in the dilepton channel at D0May 02 2011Aug 28 2011We measure the top quark mass (mt) in ppbar collisions at a center of mass energy of 1.96 TeV using dilepton ttbar->W+bW-bbar->l+nubl-nubarbbar events, where l denotes an electron, a muon, or a tau that decays leptonically. The data correspond to an integrated ... More
Search for pair production of the scalar top quark in muon+tau final statesFeb 09 2012We present a search for the pair production of scalar top quarks ($\tilde{t}_{1}$), the lightest supersymmetric partners of the top quarks, in $p\bar{p}$ collisions at a center-of-mass energy of 1.96 TeV, using data corresponding to an integrated luminosity ... More
Measurement of the W boson helicity in top quark decays using 5.4 fb^-1 of ppbar collision dataNov 30 2010Sep 20 2012We present a measurement of the helicity of the W boson produced in top quark decays using ttbar decays in the l+jets and dilepton final states selected from a sample of 5.4 fb^-1 of collisions recorded using the D0 detector at the Fermilab Tevatron ppbar ... More
IRIDE White Book, An Interdisciplinary Research Infrastructure based on Dual Electron linacs&lasersJul 30 2013This report describes the scientific aims and potentials as well as the preliminary technical design of IRIDE, an innovative tool for multi-disciplinary investigations in a wide field of scientific, technological and industrial applications. IRIDE will ... More
Long-Baseline Neutrino Facility (LBNF) and Deep Underground Neutrino Experiment (DUNE) Conceptual Design Report Volume 1: The LBNF and DUNE ProjectsJan 20 2016This document presents the Conceptual Design Report (CDR) put forward by an international neutrino community to pursue the Deep Underground Neutrino Experiment at the Long-Baseline Neutrino Facility (LBNF/DUNE), a groundbreaking science experiment for ... More
EuPRAXIA@SPARC_LAB Design study towards a compact FEL facility at LNFJan 26 2018On the wake of the results obtained so far at the SPARC\_LAB test-facility at the Laboratori Nazionali di Frascati (Italy), we are currently investigating the possibility to design and build a new multi-disciplinary user-facility, equipped with a soft ... More
Technical Design Report EuroGammaS proposal for the ELI-NP Gamma beam SystemJul 14 2014The machine described in this document is an advanced Source of up to 20 MeV Gamma Rays based on Compton back-scattering, i.e. collision of an intense high power laser beam and a high brightness electron beam with maximum kinetic energy of about 720 MeV. ... More
Decay width of light quark hybrid meson from the latticeMar 06 2006Apr 13 2006Lattice QCD with $N_f=2$ flavours of sea quark is used to explore the spectrum and decay of a $J^{PC}=1^{-+}$ spin-exotic hybrid meson. We test lattice determination of S-wave decay amplitudes at threshold using $b_1 \to \pi \omega$ where agreement with ... More
Staggered Chiral Perturbation Theory with Heavy-Light MesonsSep 08 2004We merge heavy quark effective theory with staggered chiral perturbation theory to calculate heavy-light (B, D) meson quantities. We present results at NLO for the $B(D)$ meson decay constant in the partially quenched and full QCD cases, and discuss the ... More
Transverse stability of periodic traveling waves in Kadomtsev-Petviashvili equations: A numerical studyAug 16 2011We numerically investigate transverse stability and instability of so-called cnoidal waves, i.e., periodic traveling wave solutions of the Korteweg-de Vries equation, under the time-evolution of the Kadomtsev-Petviashvili equation. In particular, we find ... More
Azimuthal decorrelation of Mueller-Navelet jets at the Tevatron and the LHCApr 25 2007Nov 05 2008We study the production of Mueller-Navelet jets at hadron colliders in the Balitsky-Fadin-Kuraev-Lipatov (BFKL) framework. We show that a measurement of the relative azimuthal angle \Delta\Phi between the jets can provide a good testing ground for corrections ... More
High-dielectric constant and wide band gap inverse silver oxide phases of the ordered ternary alloys of SiO$_{2}$, GeO$_{2}$ and SnO$_{2}$Jul 14 2006Dec 01 2006High-dielectric constant and wide band gap oxides have important technological applications. The crystalline oxide polymorphs having lattice constant compatibility to silicon are particularly desirable. One recently reported candidate is the inverse silver ... More
Single crystal growth and anisotropy of CeRuPOSep 26 2007Dec 05 2007We report on the single crystal growth of the ferromagnetic Kondo lattice system CeRuPO using a Sn flux method. Magnetic susceptibility and electrical resistivity measurements indicate strong anisotropy of this structurally layered compound. They evidence ... More
8--13 micron spectroscopy of luminous and ultraluminous infrared galaxiesMar 17 1999New moderate-resolution mid-infrared spectroscopy at 10 micron of 27 infrared galaxies is presented. The galaxies have been chosen from three 60 micron selected and one 12 micron selected complete flux-limited catalogs of galaxies; 17 of these sources ... More
Solving the mystery of IapetusApr 29 2005Jul 19 2007For a much better-founded theory, check Wing Ip, GEOPHYSICAL RESEARCH LETTERS, VOL. 33, L16203, doi:10.1029/2005GL025386, 2006 (see also
Transverse charge and magnetization densities in the nucleon's chiral peripheryOct 02 2013In the light-front description of nucleon structure the electromagnetic form factors are expressed in terms of frame-independent transverse densities of charge and magnetization. Recent work has studied the transverse densities at peripheral distances ... More
Chiral dynamics and peripheral transverse densitiesAug 07 2013In the partonic (or light-front) description of relativistic systems the electromagnetic form factors are expressed in terms of frame-independent charge and magnetization densities in transverse space. This formulation allows one to identify the chiral ... More
FIRST `Winged' and `X'-shaped Radio Source CandidatesJan 10 2007Mar 16 2008A small number of double-lobed radio galaxies (17 from our own census of the literature) show an additional pair of low surface brightness `wings', thus forming an overall `X'-shaped appearance. The origin of the wings in these radio sources is unclear. ... More
Compton X-ray and Gamma-ray Emission from Extended Radio GalaxiesApr 06 2007The extended lobes of radio galaxies are examined as sources of X-ray and gamma-ray emission via inverse Compton scattering of 3K background photons. The Compton spectra of two exemplary examples, Fornax A and Centaurus A, are estimated using available ... More
Panchromatic Views of Large-scale Extragalactic JetsDec 14 2006Highlights of recent observations of extended jets in AGN are presented. Specifically, we discuss new spectral constraints enabled by Spitzer, studies of the highest-redshift (z~4) radio/X-ray quasar jets, and a new VLBA detection of superluminal motion ... More
Series of convex functions: subdifferential, conjugate and applications to entropy minimizationJun 03 2015A formula for the sub\-differential of the sum of a series of convex functions defined on a Banach space was provided by X. Y. Zheng in 1998. In this paper, besides a slight extension to locally convex spaces of Zheng's results, we provide a formula for ... More
Torsion cohomology classes and algebraic cycles on complex projective manifoldsMar 16 2004Jan 15 2005Atiyah and Hirzebruch gave examples ofeven degree torsion classes in the singularcohomology of a smooth complex projective manifold, which arenot Poincar\'{e} dual to an algebraiccycle. We notice that the order ofthese classes are small comparedto the ... More
Modified Newtonian Mechanics from an interpolating metricJan 04 2016Jun 22 2018A few years ago Baker \cite{baker} proposed a Lema$\hat{i}$tre-Tolman metric to interpolate smoothly between the Schwarzschild metric at small scales and the Friedmann-Robertson-Walker (FRW) metric at large scales. As it stands, by implementing the Bona-Stela ... More
Elements stability: a microcosmos effect?Sep 13 2006The electronic structure of heavy elements, when described in a space-time which the metric is affected by the electromagnetic interaction, presents instabilities. These instabilities increase with the atomic number, and above a critical value, become ... More
Generating functional analysis of Minority Games with real market historiesOct 13 2004It is shown how the generating functional method of De Dominicis can be used to solve the dynamics of the original version of the minority game (MG), in which agents observe real as opposed to fake market histories. Here one again finds exact closed equations ... More
Statistical Mechanics of Recurrent Neural Networks II. DynamicsJun 01 2000A lecture notes style review of the non-equilibrium statistical mechanics of recurrent neural networks with discrete and continuous neurons (e.g. Ising, graded-response, coupled-oscillators). To be published in the Handbook of Biological Physics (North-Holland). ... More
Non-equilibrium statistical mechanics of Minority GamesMay 13 2002In this paper I give a brief introduction to a family of simple but non-trivial models designed to increase our understanding of collective processes in markets, the so-called Minority Games, and their non-equilibrium statistical mathematical analysis. ... More
NSV 13983: A New Dwarf Nova in the Period GapJun 17 2008Aims. NSV 13983 is catalogued as a dwarf nova based on a reported outburst from 2005. The system has not yet been studied spectroscopically. We attempt to confirm its nature as a dwarf nova and determine its orbital period. Methods. We derive the orbital ... More
Computation of the topological type of a real Riemann surfaceApr 21 2012We present an algorithm for the computation of the topological type of a real compact Riemann surface associated to an algebraic curve, i.e., its genus and the properties of the set of fixed points of the anti-holomorphic involution $\tau$, namely, the ... More
A new and trivial CP symmetry for extended $A_4$ flavorJan 05 2016May 18 2016The combination of $\nu_\mu$-$\nu_\tau$ exchange together with CP conjugation in the neutrino sector (known as $\mathrm{CP}^{\mu\tau}$ symmetry or $\mu\tau$-reflection) is known to predict the viable pattern: $\theta_{23}=45^\circ$, maximal Dirac CP phase ... More
Symmetric cohomology of groups as a Mackey functorDec 05 2014Symmetric cohomology of groups, defined by M. Staic in [2], is similar to the way one defines the cyclic cohomology for algebras. We show that there is a well-defined restriction, conjugation and transfer map in symmetric cohomology, which form a Mackey ... More
Scaling of the superfluid density in severely underdoped YBa2Cu3O6+yNov 20 2009Recent measurements on extremely-underdoped YBa2Cu3O6+y [Phys. Rev. Lett. 99, 237003 (2007)] have allowed the critical temperature (T_c), superfluid density [rho_0 (T << T_c)] and dc conductivity [sigma_dc (T ~ T_c)] to be determined for a series of electronic ... More
Quantum-mechanical picture of peripheral chiral dynamicsMar 06 2015The nucleon's peripheral transverse charge and magnetization densities are computed in chiral effective field theory. The densities are represented in first-quantized form, as overlap integrals of chiral light-front wave functions describing the transition ... More
Eclipsing Binary PulsarsApr 05 2004The first eclipsing binary pulsar, PSR B1957+20, was discovered in 1987. Since then, 13 other eclipsing low-mass binary pulsars have been found, 12 of these are in globular clusters. In this paper we list the known eclipsing binary pulsars and their properties, ... More
The Pulsar Population in Globular Clusters and in the GalaxyOct 15 2012Oct 23 2012In this paper, I review some of the basic properties of the pulsar population in globular clusters (GCs) and compare it with the the Galactic disk population. The neutron stars (NSs) in GCs were likely formed - and appear to continue forming - in highly ... More
Small-x QCD effects in forward-jet and Mueller-Navelet jet productionOct 20 2005Mar 07 2006We investigate small-x QCD effects in forward-jet production in deep inelastic scattering in the kinematic regime where the virtuality of the photon and the transverse momentum of the jet are two hard scales of about the same magnitude. We show that the ... More
The Gravitational Radiaton degrees of freedom in Hyperbolic Systems for Numerical RelativityAug 06 2002The gravitational radiation degrees of freedom of freedom are described in the framework of the 3+1 decomposition of spacetime. The relationship with eigenfields of the Kidder-Scheel-Teukolsky (KST) equations is established. This relationship is used ... More
Approximate solutions for N-body Hamiltonians with identical particles in D dimensionsJul 19 2013Nov 13 2013A method based on the envelope theory is presented to compute approximate solutions for $N$-body Hamiltonians with identical particles in $D$ dimensions ($D\ge 2$). In some favorable cases, the approximate eigenvalues can be analytically determined and ... More
Schur-finiteness in $λ$-ringsNov 05 2010Nov 17 2011We introduce the notion of a Schur-finite element in a $\lambda$-ring.
Pion and Kaon masses in Staggered Chiral Perturbation TheoryApr 21 2003Jul 07 2003We show how to compute chiral logarithms that take into account both the $\cO(a^2)$ taste-symmetry breaking of staggered fermions and the fourth-root trick that produces one taste per flavor. The calculation starts from the Lee-Sharpe Lagrangian generalized ... More
Heavy-Light Semileptonic Decays in Staggered Chiral Perturbation TheoryApr 05 2007Jun 26 2007We calculate the form factors for the semileptonic decays of heavy-light pseudoscalar mesons in partially quenched staggered chiral perturbation theory (\schpt), working to leading order in $1/m_Q$, where $m_Q$ is the heavy quark mass. We take the light ... More
Pseudoscalar Decay Constants in Staggered Chiral Perturbation TheoryJun 20 2003Sep 29 2003In a continuation of an ongoing program, we use staggered chiral perturbation theory to calculate the one-loop chiral logarithms and analytic terms in the pseudoscalar meson leptonic decay constants, $f_{\pi^+_5}$ and $f_{K^+_5}$. We consider the partially ... More
New construction of algebro-geometric solutions to the Camassa-Holm equation and their numerical evaluationSep 24 2011Dec 06 2011An independent derivation of solutions to the Camassa-Holm equation in terms of multi-dimensional theta functions is presented using an approach based on Fay's identities. Reality and smoothness conditions are studied for these solutions from the point ... More
Observations of Galaxy Clustering at High RedshiftNov 25 1998This paper reviews the current status of measurements of galaxy clustering at high redshifts (z > 0.3). The focus is on the inherent limitations in the observation and interpretation of the ``evolution of clustering''. It is likely that results from the ... More
Properties of light scalar mesons from lattice QCDApr 12 2006Jul 10 2006Lattice QCD with $N_f=2$ flavours of sea quark is used to explore the spectrum and decay of scalar mesons. We are able to determine the $b_1$ - $a_0$ mass difference and this leads to the conclusion that the lightest non-singlet scalar meson ($a_0$) has ... More
Radio-Quiet Quasars in the Direction of the Northern Hubble Deep FieldSep 13 2000We match quasars discovered in a multi-color survey centered on the northern Hubble Deep Field (HDF) with radio sources from an ultra-deep radio survey. Although 3 out of 12 quasars are detected at a level below 0.2 mJy at 1.4 GHz, all of the quasars ... More
Super-Massive Neutron StarsNov 30 2007We present here the results of Arecibo timing of PSR B1516+02B, a 7.95-ms pulsar in a binary system with a ~0.17 solar mass companion and an orbital period of 6.85 days located in the globular cluster M5. The eccentricity of the orbit (e = 0.14) has allowed ... More
A Multi-scale Subtraction Scheme and Partial Renormalization Group Equations in the $O(N)$-symmetric $φ^4$-theoryApr 23 1996To resum large logarithms in multi-scale problems a generalization of $\MS$ is introduced allowing for as many renormalization scales as there are generic scales in the problem. In the new \lq\lq minimal multi-scale subtraction scheme'' standard perturbative ... More