Results for "V. C. Antochi"

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Carbon nanotubes as target for directional detection of light WIMPJul 09 2017In this paper I will briefly introduce the idea of using Carbon Nanotubes (CNT) as target for the detection of low mass WIMPs with the additional information of directionality. I will also present the experimental efforts of developing a Time Projection ... More
Combined readout of a triple-GEM detectorMar 19 2018Optical readout of GEM based devices by means of high granularity and low noise CMOS sensors allows to obtain very interesting tracking performance. Space resolution of the order of tens of $\mu$m were measured on the GEM plane along with an energy resolution ... More
First results on the scalar WIMP-pion coupling, using the XENON1T experimentNov 29 2018We present first results on the scalar WIMP-pion coupling from 1 t$\times$yr of exposure with the XENON1T experiment. This interaction is generated when the WIMP couples to a virtual pion exchanged between the nucleons in a nucleus. In contrast to most ... More
First observation of two-neutrino double electron capture in $^{124}$Xe with XENON1TApr 24 2019Two-neutrino double electron capture ($2\nu$ECEC) is a second-order Weak process with predicted half-lives that surpass the age of the Universe by many orders of magnitude. Until now, indications for $2\nu$ECEC decays have only been seen for two isotopes, ... More
The XENON1T Data Acquisition SystemJun 03 2019The XENON1T liquid xenon time projection chamber is the most sensitive detector built to date for the measurement of direct interactions of weakly interacting massive particles with normal matter. The data acquisition system (DAQ) is constructed from ... More
Constraining the spin-dependent WIMP-nucleon cross sections with XENON1TFeb 08 2019We report the first experimental results on spin-dependent elastic WIMP-nucleon scattering from the XENON1T dark matter search experiment. The analysis uses the full tonne-year exposure of XENON1T to constrain the spin-dependent proton-only and neutron-only ... More
Constraining the Spin-Dependent WIMP-Nucleon Cross Sections with XENON1TFeb 08 2019Apr 30 2019We report the first experimental results on spin-dependent elastic weakly interacting massive particle (WIMP) nucleon scattering from the XENON1T dark matter search experiment. The analysis uses the full ton year exposure of XENON1T to constrain the spin-dependent ... More
XENON1T Dark Matter Data Analysis: Signal \& Background Models, and Statistical InferenceFeb 28 2019The XENON1T experiment searches for dark matter particles through their scattering off xenon atoms in a 2 tonne liquid xenon target. The detector is a dual-phase time projection chamber, which measures simultaneously the scintillation and ionization signals ... More
First results on the scalar WIMP-pion coupling, using the XENON1T experimentNov 29 2018Feb 22 2019We present first results on the scalar WIMP-pion coupling from 1 t$\times$yr of exposure with the XENON1T experiment. This interaction is generated when the WIMP couples to a virtual pion exchanged between the nucleons in a nucleus. In contrast to most ... More
XENON1T Dark Matter Data Analysis: Signal & Background Models, and Statistical InferenceFeb 28 2019Mar 01 2019The XENON1T experiment searches for dark matter particles through their scattering off xenon atoms in a 2 tonne liquid xenon target. The detector is a dual-phase time projection chamber, which measures simultaneously the scintillation and ionization signals ... More
XENON1T Dark Matter Data Analysis: Signal Reconstruction, Calibration and Event SelectionJun 11 2019The XENON1T experiment at the Laboratori Nazionali del Gran Sasso is the most sensitive direct detection experiment for dark matter in the form of weakly interacting particles (WIMPs) with masses above $6\,$GeV/$c^2$ scattering off nuclei. The detector ... More
Ground state of antiferromagnetic ordering in fullerene $C_{60}$ moleculeJan 15 2001Theoretical study of mutual orientation of fullerene $C_{60}$ molecule atom spins is presented in this work. Spin-spin interaction was described by Habbard's model. Existence of antiferromagnetic sturcture of spin sub-system in ground state is found.
H_3^(2+) molecular ion in a strong magnetic field: a triangular configurationJan 12 2000Jan 19 2000The bound state in the system of three protons and an electron (pppe) under a homogeneous strong magnetic field where the protons are situated in the vertices of an equilateral triangle perpendicular to the magnetic field lines is found. It is shown that ... More
Supercurrent and multiple singlet-doublet phase transitions of a quantum dot Josephson junction inside an Aharonov-Bohm ringOct 21 2008Jan 28 2009We study a quantum dot Josephson junction inside an Aharonov-Bohm environment. The geometry is modeled by an Anderson impurity coupled to two directly-linked BCS leads. We illustrate that the well-established picture of the low-energy physics being governed ... More
Searching for evidence of jet-cloud interaction in radio galaxies. First results for 3C 381Jan 10 2013We present results of Gemini spectroscopy and Hubble Space Telescope imaging of the 3C~381 radio galaxy. Possible ionising mechanisms for the Extended Emission-Line Region were studied through state-of-the-art diagnostic analysis employing line-ratios. ... More
A search for water masers toward extrasolar planetsFeb 17 2006Water is the most common triatomic molecule in the universe and the basis of life on Earth. Astrophysical masers have been widely studied in recent years and have been shown to be invaluable probes of the details of the environment in which they are found. ... More
"Stokes' Second Problem in High Frequency Limit. Application to Micro (Nano)- ResonatorsSep 25 2006Mar 26 2007Using kinetic equation in the relaxation approximation (RTA), we investigate a flow generated by an infinite plate oscillating with frequency $\omega$. Geometrical simplicity of the problem allows a solution in the entire range of dimensionless frequency ... More
Dilepton Production at SPS-energy Heavy Ion CollisionsJun 14 1996The production of dileptons is studied within a hadronic transport model. We investigate the sensitivity of the dilepton spectra to the initial configuration of the hadronic phase in a ultrarelativistic heavy ion collision. Possible in medium correction ... More
On free resolutions in multivariable operator theorySep 17 2001Sep 18 2001We define the notion of a free resolution of a d-tuple $(T_1, T_2, . . . T_d)$ of mutually commuting operators acting on a Hilbert space H, and that this invariant gives rise to a class of vector space complexes parametrized by points in the unit ball ... More
The combinatorics of resource sharingSep 23 2003We discuss general models of resource-sharing computations, with emphasis on the combinatorial structures and concepts that underlie the various deadlock models that have been proposed, the design of algorithms and deadlock-handling policies, and concurrency ... More
Control over adversarial packet-dropping communication networks revisitedMar 22 2014We revisit a one-step control problem over an adversarial packet-dropping link. The link is modeled as a set of binary channels controlled by a strategic jammer whose intention is to wage a `denial of service' attack on the plant by choosing a most damaging ... More
Caustics of $1/r^n$ binary gravitational lenses: from galactic haloes to exotic matterNov 25 2015Mar 07 2016We investigate the caustic topologies for binary gravitational lenses made up of two objects whose gravitational potential declines as $1/r^n$. With $n<1$ this corresponds to power-law dust distributions like the singular isothermal sphere. The $n>1$ ... More
Lorentzian worldlines and Schwarzian derivativeSep 11 1998We relate in this note the classical Schwarzian derivative to the curvature of time-like curves in Lorentz surfaces of constant curvature.
Projectively equivariant quantization and symbol calculus: noncommutative hypergeometric functionsMar 15 2001We extend projectively equivariant quantization and symbol calculus to symbols of pseudo-differential operators. An explicit expression in terms of hypergeometric functions with noncommutative arguments is given. Some examples are worked out, one of them ... More
Space of second order linear differential operators as a module over the Lie algebra of vector fieldsSep 12 1994The space of linear differential operators on a smooth manifold $M$ has a natural one-parameter family of $Diff(M)$ (and $Vect(M)$)-module structures, defined by their action on the space of tensor-densities. It is shown that, in the case of second order ... More
An extension of the Burau representation to a mapping class group associated to Thompson's group TFeb 25 2003We study some aspects of the geometric representation theory of the Thompson and Neretin groups, suggested by their analogies with the diffeomorphism groups of the circle. We prove that the Burau representation of the Artin braid groups extends to a mapping ... More
Are Spiral Disks Really Opaque ?Nov 24 1994We compare the ultra-violet, optical, and far-infrared emission for a sample of 135 spiral galaxies in order to address the widely debated problem concerning the opacity of spiral disks. We find that the re-radiation of the dust, estimated from the far-infrared ... More
Approximate Dynamic Programming via a Smoothed Linear ProgramAug 04 2009Oct 03 2009We present a novel linear program for the approximation of the dynamic programming cost-to-go function in high-dimensional stochastic control problems. LP approaches to approximate DP have typically relied on a natural `projection' of a well studied linear ... More
Polysulfanes on interstellar grains as a possible reservoir of interstellar sulphurJul 23 2012The form of depleted sulphur in dense clouds is still unknown. Until now, only two molecules, OCS and SO2, have been detected in interstellar ices but cannot account for the elemental abundance of sulphur observed in diffuse medium. Chemical models suggest ... More
The fingerprints of Photoionization and Shock-Ionization in two CSS sourcesOct 23 2015We investigate the ionization state of the Extended Emission-Line Regions (EELRs) around two compact steep-spectrum (CSS) radio galaxies, 3C~268.3 and 3C~303.1, in order to identify the contribution of photoionization and shock-ionization. We perform ... More
Self-generated electronic heterogeneity and quantum glassiness in the high temperature superconductorsOct 05 2004We present a systematic study of the spin and charge dynamics of copper oxide superconductors as a function of carrier concentration $x$. Our results portray a coherent physical picture, which reveals a quantum critical point at optimum doping ($x=x_{opt}$), ... More
The Aharonov-Bohm phase is locally generated (like all other quantum phases)Jun 08 2019Aharonov and Bohm noted that the wave-function of a charge acquires a detectable phase when superposed along two paths enclosing an infinite solenoid, even though that wave-function is non-zero exclusively where the solenoid's electric and magnetic fields ... More
Electron State Entanglement at Double IonizationMay 07 2001Dec 02 2001Electron wave function entanglement and spin reconfiguration as source of electron correlation are investigated. Properties of correlation function are shown to have the best concordance with experimental data under supposition that probability of change ... More
Mapping Among Manifolds IIMar 07 2008Mar 08 2008In a previous paper we built a modified Hamiltonian formalism to make possible explicit maps among manifolds. In this paper the modified formalism was generalized. As an application, we have built maps among spaces associated to spinors, as well as maps ... More
Physical Principles Based on Geometric PropertiesJun 22 2010Jun 23 2010In this paper we present some results obtained in a previous paper about the Cartan's approach to Riemannian normal coordinates and our conformal transformations among pseudo-Riemannian manifolds. We also review the classical and the quantum angular momenta ... More
Exact Solutions of Einstein EquationsJan 02 2001We use a metric of the type Friedmann-Robertson-Walker to obtain new exact solutions of Einstein equations for a scalar and massive field. The solutions have a permanent or transitory inflationary behavior.
On a classical correspondence between K3 surfaces IIIMay 14 2006Let $X$ be a K3 surface, and $H$ its primitive polarization of the degree $H^2=8$. The moduli space of sheaves over $X$ with the isotropic Mukai vector $(2,H,2)$ is again a K3 surface, $Y$. In math.AG/0206158 we gave necessary and sufficient conditions ... More
The motion of a charged particle in Kalusa-Klein manifoldsOct 09 2007In this paper we use Jacobi fields to describe the motion of a charged particle in the classical gravitational, electromagnetic, and Yang-Mills fields.
Mapping Among Manifolds IIINov 14 2013In two previous papers, we constructed two modified Hamiltonian formalisms to make maps among manifolds explicit. In this paper, the two modified formalisms were adapted to manifolds with local coordinates given by scalar fields, as in a classical nonlinear ... More
A Possible Origin of Dark Matter, Dark Energy, and Particle-Antiparticle AsymmetrySep 30 2010In this paper we present a possible origin of dark matter and dark energy from a solution of the Einstein's equation to a primordial universe, which was presented in a previous paper. We also analyze the Dirac's equation in this primordial universe and ... More
Atom made from charged elementary black holeJan 10 2000It is believed that there may have been a large number of black holes formed in the very early universe. These would have quantised masses. A charged ``elementary black hole'' (with the minimum possible mass) can capture electrons, protons and other charged ... More
Theory of Spike Spiral Waves in a Reaction-Diffusion SystemAug 11 1998We discovered a new type of spiral wave solutions in reaction-diffusion systems --- spike spiral wave, which significantly differs from spiral waves observed in FitzHugh-Nagumo-type models. We present an asymptotic theory of these waves in Gray-Scott ... More
A Random Search Framework for Convergence Analysis of Distributed Beamforming with FeedbackJun 18 2008Jul 13 2010The focus of this work is on the analysis of transmit beamforming schemes with a low-rate feedback link in wireless sensor/relay networks, where nodes in the network need to implement beamforming in a distributed manner. Specifically, the problem of distributed ... More
2MASS Two-color Interstellar Reddening Line in the Direction of the North America and Pelican Nebulae and the Cyg OB2 AssociationSep 16 2008The slope of the interstellar reddening line in the J-H vs. H-Ks diagram of the 2MASS survey in the direction of the North America and Pelican nebulae, the L935 dust cloud and the Cyg OB2 association is determined. The MK types were either classified ... More
Two-parameter generalization of the logarithm and exponential functions and Boltzmann-Gibbs-Shannon entropyMar 30 2007The $q$-sum $x \oplus_q y \equiv x+y+(1-q) xy$ ($x \oplus_1 y=x+y$) and the $q$-product $x\otimes_q y \equiv [x^{1-q} +y^{1-q}-1]^{\frac{1}{1-q}}$ ($x\otimes_1 y=x y$) emerge naturally within nonextensive statistical mechanics. We show here how they lead ... More
Deforming the Lie algebra of vector fields on $S^1$ inside the Poisson algebra on $\dot T^*S^1$Jul 07 1997We study deformations of the standard embedding of the Lie algebra $\Vect(S^1)$ of smooth vector fields on the circle, into the Lie algebra of functions on the cotangent bundle $T^*S^1$ (with respect to the Poisson bracket). We consider two analogous ... More
The interleaved multichromatic number of a graphSep 23 2003For $k\ge 1$, we consider interleaved $k$-tuple colorings of the nodes of a graph, that is, assignments of $k$ distinct natural numbers to each node in such a way that nodes that are connected by an edge receive numbers that are strictly alternating between ... More
High order Nyström methods for transmission problems for Helmholtz equationOct 22 2015May 12 2016We present superalgebraic compatible Nystr\"om discretizations for the four Helmholtz boundary operators of Calder\'{o}n's calculus on smooth closed curves in 2D. These discretizations are based on appropriate splitting of the kernels combined with very ... More
Conformally equivariant quantizationJan 27 1998Feb 25 2000Let $(M,g)$ be a pseudo-Riemannian manifold and $F_\lambda(M)$ the space of densities of degree $\lambda$ on $M$. We study the space $D^2_{\lambda,\mu}(M)$ of second-order differential operators from $F_\lambda(M)$ to $F_\mu(M)$. If $(M,g)$ is conformally ... More
Scalar filed evolution and area spectrum for Lovelock-AdS black holesOct 01 2013Oct 04 2013We study the modes of evolution of massless scalar fields in the asymptotically AdS spacetime surrounding maximally symmetric black holes of large and intermediate size in the Lovelock model. It is observed that all modes are purely damped at higher orders. ... More
Non-thermal recombination - a neglected source of flare hard X-rays and fast electron diagnosticJun 19 2007Feb 05 2008Context. Flare Hard X-Rays (HXRs) from non-thermal electrons are commonly treated as solely bremsstrahlung (f-f), recombination (f-b) being neglected. This assumption is shown to be substantially in error, especially in hot sources, mainly due to recombination ... More
Manifestations of a spatial variation of fundamental constants on atomic clocks, Oklo, meteorites, and cosmological phenomenaAug 24 2010The remarkable detection of a spatial variation in the fine-structure constant, alpha, from quasar absorption systems must be independently confirmed by complementary searches. In this letter, we discuss how terrestrial measurements of time-variation ... More
Astronomical and laboratory searches for space-time variation of fundamental constantsSep 20 2010We review recent activity searching for variations in the fundamental constants of nature in quasar absorption spectra and in the laboratory. While research in this direction has been ongoing for many decades, the topic has recently been stimulated by ... More
Analysis of Boundary Conditions for Crystal Defect Atomistic SimulationsJun 22 2013May 23 2016Numerical simulations of crystal defects are necessarily restricted to finite computational domains, supplying artificial boundary conditions that emulate the effect of embedding the defect in an effectively infinite crystalline environment. This work ... More
Time reversal violating Magnetic Quadrupole Moment in heavy deformed nucleiOct 05 2018Dec 10 2018The existence of permanent electric dipole moments (EDMs) and magnetic quadrupole moments (MQMs) violate both time reversal invariance ($T$) and parity ($P$). Following the $CPT$ theorem they also violate combined $CP$ symmetry. Nuclear EDM are completely ... More
Effect of atomic electric quadrupole moment on positron bindingJun 05 2014Effect of the electric quadrupole moment, $Q$, is studied for positron-atom bound systems. It is demonstrated that for $Q >50$ a.u. the electric quadrupole potential is sufficiently strong to bind positron (or electron) even in the absence of the dipole ... More
Relations between matrix elements of different weak interactions and interpretation of the PNC and EDM measurements in atoms and moleculesSep 28 2011Jan 25 2012The relations between matrix elements of different P- and T-odd weak interactions are derived. We demonstrate that similar relations hold for parity nonconserving (PNC) transition amplitudes and electron electric dipole moments (EDM) of atoms and molecules. ... More
Theoretical study of electron structure of superheavy elements with open $6d$-shell, Sg, Bh, Hs and MtFeb 18 2019We use recently developed efficient versions of the configuration interaction method to perform {\em ab initio} calculations of the spectra of superheavy elements seaborgium (Sg, $Z=106$), bohrium (Bh, $Z=107$), hassium (Hs, $Z=108$) and meitnerium (Mt, ... More
Constraints on spin-3/2 and excited spin-1/2 fermions coming from the leptonic Z0-partial widthSep 01 1993We consider effective interactions among excited spin-1/2 and spin-3/2 leptons with the usual ones. Assuming that these new leptons are lighter than the Z0 we will study the constraints on their masses and compositeness scale coming from the leptonic ... More
Global symmetries: matter from geometry, hoop conjecture, and cosmic censorshipSep 04 2003Dec 30 2003We show that four-dimensional Lorentzian metrics admitting a global spacelike Lie group of isometries, $G_{1}={\mathbb R}$, which obey the Einstein equations for vacuum and certain types of matter, cannot contain apparent horizons. The assumed global ... More
Unpolarized radiative cylindrical spacetimes: Trapped surfaces and quasilocal energyDec 30 2002We consider the most general vacuum cylindrical spacetimes, which are defined by two global, spacelike, commuting, non-hypersurface-orthogonal Killing vector fields. The cylindrical waves in such spacetimes contain both + and $\times$ polarizations, and ... More
Galaxy downsizing evidenced by hybrid evolutionary tracksAug 27 2010Nov 26 2011An unified picture of stellar and halo mass build-up as a function of mass is presented. Inferred stellar-dark halo mass relations of galaxies, Ms-Mh, out to z=4 together with average LCDM halo mass aggregation histories (MAHs) are used for inferring ... More
The size evolution of galaxy discs formed within Lambda Cold Dark Matter haloesMar 31 2009Apr 22 2009By means of galaxy evolutionary models, we explore the direct consequences of the LCDM cosmogony on the size evolution of galactic discs, avoiding intentionally the introduction of intermediate (uncertain) astrophysical processes. Based on the shape of ... More
On the origin of the color Tully-Fisher and color-magnitude relations of disk galaxiesFeb 16 2000We propose and show that the dependence of the internal face-on dust absorption upon B-band luminosity reported by Wang & Heckman (1996) for a sample of late-type galaxies may explain the empirical color-magnitude and color Tully-Fisher relations of disk ... More
On the Formation of Bulges and Elliptical Galaxies in the Cosmological ContextAug 17 1998We study the formation of hot spheroidal systems within the frame of a scenario where galaxy formation and evolution is related to the gentle mass aggregation history and primordial angular momentum of protogalaxies, both defined by the cosmological initial ... More
Physical processes behind the morphological Hubble sequenceMar 25 2003Jun 16 2003The study of formation and evolution of galaxies is reviewed, making emphasis on the physical factors which are important to understand the origin of the galaxy Hubble sequence. We concentrate on predictions of the hierarchical Cold Dark Matter (CDM) ... More
Formation and evolution of galaxy disks: what is wrong with CDM?Feb 09 2002We find that the density distribution of high and low surface brightness (SB) galaxy disks formed within LCDM halos under the assumption of detailed angular momentum conservation is in rough agreement with observations. The luminous-to-dark matter ratio ... More
Structure, dynamics and evolution of disk galaxies in a hierarchical formation scenarioOct 01 1999Using galaxy evolutionary models in a hierarchical formation scenario, we predict the structure, dynamics and evolution of disk galaxies in a LCDM universe. Our models include star formation and hydrodynamics of the ISM. We find that the Tully-Fisher ... More
Disk galaxy formation and evolution: models up to intermediate redshiftsOct 20 1998Making use of a seminumerical method we develop a scenario of disk galaxy formation and evolution in the framework of inflationary cold dark matter (CDM) cosmologies. Within the virializing dark matter halos, disks in centrifugal equilibrium are built-up ... More
Dirac Quasinormal modes of MSW black holesJan 15 2014In this paper we study the Dirac quasinormal modes of an uncharged 2 + 1 black hole proposed by Mandal et. al and referred to as MSW black hole in this work. The quasi- normal mode is studied using WKB approximation method. The study shows that the imaginary ... More
Scattering of Scalar Field by an Extended Black Hole in F(R) gravityJan 15 2014In this work we have studied the scattering of scalar field around an extended black hole in F(R) gravity using WKB method. We have obtained the wave function in different regions such as near the horizon region, away from horizon and far away from horizon ... More
Evolution of electromagnetic and Dirac perturbations around a black hole in Horava gravityOct 04 2010May 16 2011The evolution of electromagnetic and Dirac perturbations in the spacetime geometry of Kehagias-Sfetsos(KS) black hole in the deformed Horava-Lifshitz(HL) gravity is investigated and the associated quasinormal modes are evaluated using time domain integration ... More
What can be learned from the schematic mode-coupling approach to experimental data ?Apr 10 2002We propose a detailed investigation of the schematic mode-coupling approach to experimental data, a method based on the use of simple mode-coupling equations to analyze the dynamics of supercooled liquids. Our aim here is to clarify different aspects ... More
On the spectral distribution of photons between planar interfacesMay 08 2014Using a phenomenological approach to field quantization, an expression for the Keldysh function of photons between two planar interfaces (Casimir geometry) is found for any stationary quantum state of the two bodies. The case of one interface sliding ... More
Geometrothermodynamics of BTZ black hole in new massive gravityJun 20 2016We investigate the thermodynamics as well as thermodynamic geometry of chargeless BTZ black hole solution in new massive gravity. Phase structure and thermodynamic stability of the system is analyzed using the Geometrothermodynamic approach. The phase ... More
On The Leptons MassesDec 05 2007Jan 22 2008In this paper we present a connection between the results obtained from a semiclassical study of a relativistic, two-body system, and the leptons masses. Some possible consequences are also discussed.
Asteroseismic modelling of the two F-type hybrid pulsators KIC10080943A and KIC10080943BMay 25 2016Jun 08 2016Pulsating binary stars are ideal targets for testing the theory of stellar structure and evolution. Fundamental parameters can be derived to high precision from binary modelling and provide crucial constraints for seismic modelling. High-order gravity ... More
Generating Synthetic Data for Text RecognitionAug 15 2016Generating synthetic images is an art which emulates the natural process of image generation in a closest possible manner. In this work, we exploit such a framework for data generation in handwritten domain. We render synthetic data using open source ... More
Light radioactive nuclei capture reactions with phenomenological potential modelsDec 01 2009Light radioactive nuclei play an important role in many astrophysical environments. Due to very low cross sections of some neutron and proton capture reactions by these radioactive nuclei at energies of astrophysical interest, direct laboratory measurements ... More
Is the tetraneutron a bound dineutron-dineutron molecule?Dec 13 2002Sep 03 2003In light of a new experiment which claims a positive identification, we discuss the possible existence of the tetraneutron. We explore a novel model based on a dineutron-dineutron molecule. We show that this model is not able to explain the tetraneutron ... More
Nonassociative strict deformation quantization of C*-algebras and nonassociative torus bundlesDec 10 2010Jun 02 2012In this paper, we initiate the study of nonassociative strict deformation quantization of C*-algebras with a torus action. We shall also present a definition of nonassociative principal torus bundles, and give a classification of these as nonassociative ... More
Kinematical twist-3 effects in DVCS as a quark spin rotationJun 05 2001We point out that the kinematical twist-3 contributions to the DVCS amplitude, required to restore electromagnetic gauge invariance of the twist-2 amplitude up to O(t/q^2), can be understood as a spin rotation applied to the twist-2 quark density matrix ... More
The Experimental Status of GlueballsDec 03 2008Mar 02 2009Glueballs and other resonances with large gluonic components are predicted as bound states by Quantum Chromodynamics (QCD). The lightest (scalar) glueball is estimated to have a mass in the range from 1 to 2 GeV/c**2; a pseudoscalar and tensor glueball ... More
A frequentist analysis of solar neutrino dataDec 05 2000We present a Monte Carlo analysis in terms of neutrino oscillations of the total rates measured in solar neutrino experiments in the framework of frequentist statistics. We show that the goodness of fit and the confidence level of the allowed regions ... More
Discriminating hadronic and quark stars through gravitational waves of fluid pulsation modesOct 02 2013We investigate non-radial oscillations of hadronic, hybrid and pure self-bound strange quark stars with maximum masses above the mass of the recently observed massive pulsars PSR J1614-2230 and PSR J0348-0432 with $M \approx 2 M_{\odot}$. For the hadronic ... More
Composite system in deformed space with minimal lengthJun 01 2009Nov 18 2009For composite systems made of $N$ different particles living in a space characterized by the same deformed Heisenberg algebra, but with different deformation parameters, we define the total momentum and the center-of-mass position to first order in the ... More
Harmonic oscillator with nonzero minimal uncertainties in both position and momentum in a SUSYQM frameworkJun 18 2003Aug 22 2003In the context of a two-parameter $(\alpha, \beta)$ deformation of the canonical commutation relation leading to nonzero minimal uncertainties in both position and momentum, the harmonic oscillator spectrum and eigenvectors are determined by using techniques ... More
Spectral analysis of YSOs and other emission-line stars in the North America and Pelican nebulae regionNov 23 2009Far red spectra for 34 stars with V magnitudes between 15 and 18 in the direction of the North America and Pelican nebulae (NAP) star-forming region are obtained. Some of these stars were known earlier as emission-line objects, others were suspected as ... More
Some arguments in support of the association of PSR B1706-44 with the supernova remnant G343.1-2.3Nov 22 2001We present some arguments in support of the association of the pulsar PSR B1706-44 with the supernova remnant G343.1-2.3, based on the idea that these objects could be the result of a supernova explosion within a mushroom-like cavity (created by the supernova ... More
PSR B 1706-44 and the SNR G 343.1-2.3 as the remnants of a cavity supernova explosionAug 05 2002The possible association of the supernova remnant (SNR) G 343.1-2.3 with the pulsar PSR B 1706-44 (superposed on the arclike "shell" of the SNR) has been questioned by some authors on the basis of an inconsistency between the implied and measured (scintillation) ... More
Mapping and Embedding of Two Metrics Associated with Dark Matter, Dark Energy, and Ordinary MatterOct 29 2010In this paper we build a mapping between two different metrics and embed them in a flat manifold. One of the metrics represents the ordinary matter, and the other describes the dark matter, the dark energy, and the particle-antiparticle asymmetry. The ... More
Mapping among manifolds 1Feb 18 2008In this paper we have build the modified Hamiltonian formalism for geometric objects like the Jacobi fields and metric tensors. In this approach Jacobi fields and metric tensors are mapped among manifold. As an application, we have mapped a general n-dimensional ... More
Conformal Form of Pseudo-Riemannian Metrics by Normal Coordinate Transformations IIDec 19 2012In this paper, we have reintroduced a new approach to conformal geometry developed and presented in two previous papers, in which we show that all n-dimensional pseudo-Riemannian metrics are conformal to a flat n-dimensional manifold as well as an n-dimensional ... More
First-Principles Theory of Competing Order Types, Phase Separation, and Phonon Scattering in Thermoelectric Pb-Sb-Ag-Te AlloysMar 07 2008Using a first-principles cluster expansion, we shed light on the solid-state phase diagram and structure of the recently discovered high-performance thermoelectrics, Pb-Ag-Sb-Te alloys. The observed nanoscale inhomogeneities are shown to be coherent precipitates ... More
Scenarios of domain pattern formation in a reaction-diffusion systemJul 11 1996We performed an extensive numerical study of a two-dimensional reaction-diffusion system of the activator-inhibitor type in which domain patterns can form. We showed that both multidomain and labyrinthine patterns may form spontaneously as a result of ... More
Special complex manifoldsOct 19 1999Nov 05 2001We introduce the notion of a special complex manifold: a complex manifold (M,J) with a flat torsionfree connection \nabla such that (\nabla J) is symmetric. A special symplectic manifold is then defined as a special complex manifold together with a \nabla-parallel ... More
Quasinormal Modes of Lovelock Black HolesMay 21 2014The quasinormal modes of metric perturbations in asymptotically flat black hole spacetimes in the Lovelock model are calculated for different spacetime dimensions and higher orders of curvature. It is analytically established that in the asymptotic limit ... More
Learning through experimenting: an original way of teaching geometrical opticsSep 26 2016Over the past 10 years, we have developed at University Paris Sud a first year course on geometrical optics centered on experimentation. In contrast with the traditional top-down learning structure usually applied at university, in which practical sessions ... More
Combining configuration interaction with perturbation theory for atoms with large number of valence electronsNov 01 2016A version of the configuration interaction (CI) method is developed which treats highly excited many-electron basis states perturbatively, so that their inclusion does not affect the size of the CI matrix. This removes, at least in principle, the main ... More
Atoms which can bind positronsAug 03 2013Feb 01 2014Calculations of the positron binding energies to all atoms in the periodic table are presented and atoms where the positron-atom binding actually exists are identified. The results of these calculations and accurate calculations of other authors (which ... More