Results for "J. Osvaldo Gonzalez-Hernandez"

total 176497took 0.15s
Extraction of Generalized Parton Distribution Observables from Deeply Virtual Electron Proton Scattering ExperimentsMar 13 2019We provide the general expression of the cross section for exclusive deeply virtual photon electroproduction from a spin 1/2 target using current parameterizations of the off-forward correlation function in a nucleon for different beam and target polarization ... More
Surfaces in $mathbb{R}^4$ with constant principal angles with respect to a planeMay 09 2011We study surfaces in $\R^4$ whose tangent spaces have constant principal angles with respect to a plane. Using a PDE we prove the existence of surfaces with arbitrary constant principal angles. The existence of such surfaces turns out to be equivalent ... More
On the mass of the neutron star in Cyg X-2Oct 23 2009We present new high resolution spectroscopy of the low mass X-ray binary Cyg X-2 which enables us to refine the orbital solution and rotational broadening of the donor star. In contrast with Elebert et al (2009) we find a good agreement with results reported ... More
Chemical Tagging of FGK Stars: Testing Membership to Young Stellar Kinematics GroupsSep 11 2015In this contribution talk we summarize the results of our ongoing project of detailed analysis of the chemical content (chemical tagging) as a promising powerful method to provide clear constraints on the membership of FGK kinematic candidates to stellar ... More
The Black Hole Binary Nova Scorpii 1994 (GRO J1655-40): An improved chemical analysisMay 18 2007Mar 10 2009The chemical analysis of secondary stars of low mass X-ray binaries provides an opportunity to study the formation processes of compact objects, either black holes or neutron stars. Following the discovery of overabundances of $\alpha$-elements in the ... More
A phenomenological analysis of azimuthal asymmetries in unpolarized semi-inclusive deep inelastic scatteringFeb 14 2015Apr 03 2015We present a phenomenological analysis of the cos-phi and cos-2phi asymmetries in unpolarized semi-inclusive deep inelastic scattering, based on the recent multidimensional data released by the COMPASS and HERMES Collaborations. In the TMD framework, ... More
Activity induced by Gravitational Interaction in Galaxy PairsSep 09 2008A systematic study of the nuclear emission of a sample of 97 spirals in isolated galaxy pairs with mixed morphology (E+S) shows that: 1) AGN activity is found in 40% of the spiral galaxies in these pairs, 2) Only one out of the 39 AGN found has type 1 ... More
Challenges with Large Transverse Momentum in Semi-Inclusive Deeply Inelastic ScatteringAug 13 2018Dec 12 2018We survey the current phenomenological status of semi-inclusive deep inelastic scattering at moderate hard scales and in the limit of very large transverse momentum. As the transverse momentum becomes comparable to or larger than the overall hard scale, ... More
On explicit inversion of a subclass of operators with $D$-difference kernels and Weyl theory of the corresponding canonical systemsMay 11 2009Explicit inversion formulas for a subclass of integral operators with $D$-difference kernels on a finite interval are obtained. A case of the positive operators is treated in greater detail. An application to the inverse problem to recover canonical system ... More
Large Transverse Momentum in Semi-Inclusive Deeply Inelastic Scattering Beyond Lowest OrderMar 04 2019Motivated by recently observed tension between $O\left(\alpha_s^2\right)$ calculations of very large transverse momentum dependence in both semi-inclusive deep inelastic scattering and Drell-Yan scattering, we repeat the details of the calculation through ... More
Extremely metal-poor stars from the SDSSSep 17 2008We give a progress report about the activities within the CIFIST Team related to the search for extremely metal-poor stars in the Sloan Digital Sky Survey's spectroscopic catalog. So far the search has provided 25 candidates with metallicities around ... More
Low X-ray Luminosity Galaxy Clusters. III: Weak Lensing Mass Determination at 0.18 $<$ z $<$ 0.70Apr 13 2015Apr 15 2015This is the third of a series of papers of low X-ray luminosity galaxy clusters. In this work we present the weak lensing analysis of eight clusters, based on observations obtained with the Gemini Multi-Object Spectrograph in the $g'$, $r'$ and $i'$ passbands. ... More
Phase-field models in interfacial pattern formation out of equilibriumMay 03 2003The phase-field method is reviewed from the general perspective of converting a free boundary problem into a set of coupled partial differential equations. Its main advantage is that it avoids front tracking by using phase fields to locate the fronts. ... More
Sidebranching induced by external noise in solutal dendritic growthJan 23 2001We have studied sidebranching induced by fluctuations in dendritic growth. The amplitude of sidebranching induced by internal (equilibrium) concentration fluctuations in the case of solidification with solutal diffusion is computed. This amplitude turns ... More
Chemical tagging of the Ursa Major moving group: A northern selection of FGK starsSep 08 2014Stellar kinematic groups are kinematical coherent groups of stars which might share a common origin.These groups spread through the Galaxy over time due to tidal effects caused by Galactic rotation and disc heating.However, the chemical information survives ... More
3D strain in 2D materials: Experimental test in unsupported monolayer graphene under pressureFeb 07 2019Previous Raman measurements on supported graphene under high pressure reported a very different shift rate of in-plane phonon frequency of graphene (16 cm$^{-1}$GPa$^{-1}$) from graphite (4.7 cm$^{-1}$GPa$^{-1}$), implying very different in-plane anharmonicity ... More
A new way to infer variations of the seismic solar radiusFeb 06 2009We show that the mean phase of waves propagating all the way from the far side of the Sun to the front side, as measured by seismic holography, varies with time. The change is highly anticorrelated with solar cycle activity and is consistent with other ... More
Solar analogs with and without planets: T$_c$ trends and galactic evolutionJan 03 2015Jan 06 2015We explore a sample of 148 solar-like stars to search for a possible correlation between the slopes of the abundance trends versus condensation temperature (known as the Tc slope) both with stellar parameters and Galactic orbital parameters in order to ... More
Volatiles and refratories in solar analogs: no terrestial planet connectionNov 29 2010We have analysed very high-quality HARPS and UVES spectra of 95 solar analogs, 24 hosting planets and 71 without detected planets, to search for any possible signature of terrestial planets in the chemical abundances of volatile and refractory elements ... More
X-ray long-term variations in the low-luminosity AGN NGC835 and its circumnuclear emissionNov 05 2015Obscured active galactic nuclei (AGNs) are thought to be very common in the Universe. Observations and surveys have shown that the number of sources increases for near galaxies and at the low-luminosity regime (the so-called LLAGNs). Furthermore, many ... More
Interference Spins: Scheduling of Multiple Interfering Two-Way Wireless LinksJan 06 2015Feb 04 2015Two-way is a dominant mode of communication in wireless systems. Departing from the tradition to optimize each transmission direction separately, recent work has demonstrated that, for time-division duplex (TDD) systems, optimizing the schedule of the ... More
A survey for pulsating subdwarf B stars with the Nordic Optical TelescopeJan 20 2010A search programme for pulsating subdwarf B stars was conducted with the Nordic Optical Telescope on La Palma over 59 nights between 1999 and 2009. The purpose of the programme was to significantly extend the number of rapidly pulsating sdB stars to better ... More
Doppler and modulation tomography of XTE J1118+480 in quiescenceMay 11 2009We present Doppler and modulation tomography of the X-ray nova XTE J1118+480 with data obtained during quiescence using the 10-m Keck II telescope. The hot spot where the gas stream hits the accretion disc is seen in H-Alpha, H-Beta, He I Lambda-5876, ... More
Observations of Chiral Odd GPDs and their ImplicationsSep 28 2013Our original suggestion to investigate exclusive $\pi^0$ electroproduction as a method for extracting the tensor charge, transversity, and other quantities related to chiral odd generalized parton distributions from cross section and asymmetry data is ... More
Flexible Parametrization of Generalized Parton Distributions from Deeply Virtual Compton Scattering ObservablesDec 16 2010Feb 16 2011We present a physically motivated parametrization of the chiral-even generalized parton distributions in the non-singlet sector obtained from a global analysis using a set of available experimental data. Our analysis is valid in the kinematical region ... More
Flavor dependence of chiral odd generalized parton distributions and the tensor charge from the analysis of combined $π^0$ and $η$ exclusive electroproduction dataJan 02 2014Using a physically motivated parameterization based on the reggeized diquark model we perform a flavor separation of the chiral-odd generalized parton distributions obtained from both $\pi^0$ and $\eta$ exclusive electroproduction. In our approach we ... More
Easy as $π^o$: On the Interpretation of Recent Electroproduction ResultsJan 29 2012Jul 02 2012Exclusive $\pi^o$ electroproduction from nucleons was first suggested by Ahmad, Goldstein and Liuti for extracting from experimental data the tensor charge, transversity and other quantities related to chiral odd combinations of generalized parton distributions. ... More
MHD Remote Numerical Simulations: Evolution of Coronal Mass EjectionsDec 22 2008Coronal mass ejections (CMEs) are solar eruptions into interplanetary space of as much as a few billion tons of plasma, with embedded magnetic fields from the Sun's corona. These perturbations play a very important role in solar--terrestrial relations, ... More
Error estimates for splitting methods based on AMF-Runge-Kutta formulas for the time integration of advection diffusion reaction PDEsJan 12 2015The convergence of a family of AMF-Runge-Kutta methods (in short AMF-RK) for the time integration of evolutionary Partial Differential Equations (PDEs) of Advection Diffusion Reaction type semi-discretized in space is considered. The methods are based ... More
Invariant Differential Equations and the Adler-Gel'fand-Dikii BracketMar 29 1996In this paper we find an explicit formula for the most general vector evolution of curves on $RP^{n-1}$ invariant under the projective action of $SL(n,R)$. When this formula is applied to the projectivization of solution curves of scalar Lax operators ... More
Connection between maximum-work and maximum-power thermal cyclesAug 27 2013We propose a new connection between maximum-power Curzon-Ahlborn thermal cycles and maximum-work reversible cycles. This linkage is built through a mapping between the exponents of a class of heat transfer laws and the exponents of a family of heat capacities ... More
Meridional Circulation During the Extended Solar Minimum: Another Component of the Torsional Oscillation?Mar 08 2010We show here a component of the meridional circulation developing at medium-high latitudes (40-50 degrees) before the new solar cycle starts. Like the torsional oscillation of the zonal flows, this extra circulation seems to precede the onset of magnetic ... More
Spatial Cross Spectrum: Reducing Incoherent Convective Background of Resolved Heloseismic InstrumentsOct 09 2008Measurements of low-order p modes and gravity modes are perturbed by the solar convective background. Such perturbation increases below 2mHz for intensity measurements and 1mHz for velocity measurements. While the low-degree modes have large spatial scales, ... More
Reduction Signals Method Preserving Spatial and Temporal CapabilitiesJun 22 2018In gamma ray imaging, a scintillation crystal is typically used to convert the gamma radiation into visible light. Photosensors are used to transform this light into measurable signals. Several types of photosensors are currently in use depending on the ... More
Exploring the alpha-enhancement of metal-poor planet-hosting stars. The Kepler and HARPS samplesSep 27 2012Nov 07 2012Recent studies showed that at low metallicities Doppler-detected planet-hosting stars have preferably high alpha-content and belong to the thick disk. We used the reconnaissance spectra of 87 Kepler planet candidates and data available from the HARPS ... More
A system of three transiting super-Earths in a cool dwarf starJan 18 2018Mar 13 2018We present the detection of three super-Earths transiting the cool star LP415-17, monitored by K2 mission in its 13th campaign. High resolution spectra obtained with HARPS-N/TNG showed that the star is a mid-late K dwarf. Using spectral synthesis models ... More
The Pristine survey II: a sample of bright stars observed with FEROSMay 29 2017Extremely metal-poor (EMP) stars are old objects formed in the first Gyr of the Universe. They are rare and, to select them, the most successful strategy has been to build on large and low-resolution spectroscopic surveys. The combination of narrow- and ... More
Kinematics and chemical properties of the Galactic stellar populations. The HARPS FGK dwarfs sampleApr 09 2013Apr 10 2013(Abridged) We analyze chemical and kinematical properties of about 850 FGK solar neighborhood long-lived dwarfs observed with the HARPS high-resolution spectrograph. The stars in the sample have logg > 4 dex, 5000 < Teff < 6500 K, and -1.39 < [Fe/H] < ... More
Stars with and without planets: Where do they come from?Oct 28 2014A long and thorough investigation of chemical abundances of planet-hosting stars that lasted for more than a decade has finally beared fruit. We explore a sample of 148 solar-like stars to search for a possible correlation between the slopes of the abundance ... More
On the origin of stars with and without planets. Tc trends and clues to Galactic evolutionApr 17 2014We explore a sample of 148 solar-like stars to search for a possible correlation between the slopes of the abundance trends versus condensation temperature (known as the Tc slope) with stellar parameters and Galactic orbital parameters in order to understand ... More
Source Coding with in-Block Memory and Causally Controllable Side InformationJan 05 2013The recently proposed set-up of source coding with a side information "vending machine" allows the decoder to select actions in order to control the quality of the side information. The actions can depend on the message received from the encoder and on ... More
GIARPS@TNG GIANO-B & HARPS-N together for a wider wavelength range spectroscopyJul 14 2017Jul 18 2017Since 2012, thanks to the installation of the high resolution echelle spectrograph in the optical range HARPS-N, the Italian telescope TNG (La Palma) became one of the key facilities for the study of the extrasolar planets. In 2014 TNG also offered GIANO ... More
A theory of superconductivity in multi-walled carbon nanotubesMar 10 2006Jun 26 2006We devise an approach to describe the electronic instabilities of doped multi-walled nanotubes, where each shell has in general a manifold of Fermi points. Our analysis relies on the scale dependence of the different scattering processes, showing that ... More
Na I and H$α$ absorption features in the atmosphere of MASCARA-2b/KELT-20bMay 08 2018We have used the HARPS-North high resolution spectrograph ($\mathcal{R}$=115 000) at TNG to observe one transit of the highly irradiated planet MASCARA-2b/KELT-20b. Using only one transit observation, we are able to clearly resolve the spectral features ... More
A general theory for irreversible thermodynamicsNov 26 2015We demonstrate that irreversibility arises from the principle of microscopic reversibility and the presence of memory in the time evolution of a single copy of a system driven by a protocol. We introduce microscopic reversibility by using the concept ... More
Abundance trend with condensation temperature for stars with different Galactic birth placesJun 15 2016During the past decade, several studies reported a correlation between chemical abundances of stars and condensation temperature (also known as Tc trend). However, the real astrophysical nature of this correlation is still debated. The main goal of this ... More
Temperature dependent surface relaxation for Al(110) and Mg(10-10) studied by orbital free ab initio molecular dynamicsJun 06 2006We have performed orbital free ab initio molecular dynamics simulations in order to study the thermal behaviour of two open surfaces of solid metallic systems, namely the (110) face of fcc Al and the (10-10) face of hcp Mg. Our results reproduce qualitatively ... More
$ζ^2$ Ret, its debris disk, and its lonely stellar companion $ζ^1$ Ret. Different $T_{\mathrm{c}}$ trends for different spectraMay 06 2016Several studies have reported a correlation between the chemical abundances of stars and condensation temperature (known as Tc trend). Very recently, a strong Tc trend was reported for the $\zeta$ Reticuli binary system, which consists of two solar analogs. ... More
A general framework for microscopically reversible processes with memoryNov 25 2015Oct 25 2016Statistical Mechanics deals with ensembles of microstates that are compatible with fixed constraints and that on average define a thermodynamic macrostate. The evolution of a small system is normally subjected to changing constraints and involve a stochastic ... More
Coulomb screening and electronic instabilities of small-diameter (5,0) nanotubesJun 24 2005Jul 15 2005We investigate the instabilities that may lead to the breakdown of the Luttinger liquid in the small-diameter (5,0) nanotubes, paying attention to the competition between the effective interaction mediated by phonon-exchange and the Coulomb interaction. ... More
Electronic instabilities in 3D arrays of small-diameter (3,3) carbon nanotubesOct 21 2005We investigate the electronic instabilities of the small-diameter (3,3) carbon nanotubes by studying the low-energy perturbations of the normal Luttinger liquid regime. The bosonization approach is adopted to deal exactly with the interactions in the ... More
Jacobi osculating rank and isotropic geodesics on naturally reductive 3-manifoldsDec 13 2007We study the Jacobi osculating rank of geodesics on naturally reductive homogeneous manifolds and we apply this theory to the 3-dimensional case. Here, each non-symmetric, simply connected naturally reductive 3-manifold can be given as a principal bundle ... More
Identifying the best iron-peak and $α$-capture elements for chemical tagging: The impact of the number of lines on measured scatterSep 08 2015The main goal of this work is to explore which elements carry the most information about the birth origin of stars and as such that are best suited for chemical tagging. We explored different techniques to minimize the effect of outlier value lines in ... More
Partonic Picture of Generalized Transverse Momentum DistributionsSep 26 2013We argue that due to parity constraints, the helicity combination of the purely momentum space counterparts of the Wigner distributions -- the generalized transverse momentum distributions -- that describes the configuration of an unpolarized quark in ... More
Multiple Multicasts with the Help of a RelayFeb 18 2009The problem of simultaneous multicasting of multiple messages with the help of a relay terminal is considered. In particular, a model is studied in which a relay station simultaneously assists two transmitters in multicasting their independent messages ... More
Interpretation of the Flavor Dependence of Nucleon Form Factors in a Generalized Parton Distribution ModelJun 08 2012Sep 26 2013We give an interpretation of the $u$ and $d$ quarks contributions to the nucleon electromagnetic form factors for values of the four-momentum transfer in the multi-GeV region where flavor separated data have been recently made available. The data show, ... More
Identification of Observables for Quark and Gluon Orbital Angular MomentumDec 01 2014A new debate has recently arisen on the subject of orbital angular momentum in QCD, in particular on its observability and on its partonic interpretation. Orbital momentum can be defined in QCD using two different decomposition schemes that yield a kinetic ... More
On the Observability of the Quark Orbital Angular Momentum DistributionOct 18 2013Mar 18 2014We argue that due to Parity constraints, the helicity combination of the purely momentum space counterparts of the Wigner distributions -- the generalized transverse momentum distributions -- that describes the configuration of an unpolarized quark in ... More
Unveiling the physics of low luminosity AGN through X-ray variability: LINER versus Seyfert 2Mar 29 2016X-ray variability is very common in active galactic nuclei (AGN), but these variations may not occur similarly in different families of AGN. We aim to disentangle the structure of low ionization nuclear emission line regions (LINERs) compared to Seyfert ... More
The X-ray variability of Seyfert 1.8/1.9 galaxiesMar 15 2017Seyfert 1.8/1.9 are sources showing weak broad H-alpha components in their optical spectra. We aim at testing whether Seyfert 1.8/1.9 have similar properties at UV and X-ray wavelengths to Seyfert 2. We use the 15 Seyfert 1.8/1.9 in the Veron Cetty and ... More
On the formation and the stability of suspended transition metal monatomic chainsAug 09 2007We present a Tight-Binding Molecular Dynamics investigation of the stability, the geometrical and the electronic structure of suspended monatomic transition metal chains. We show that linear and stable monatomic chains are formed at temperature equal ... More
Extending the OpenAI Gym for robotics: a toolkit for reinforcement learning using ROS and GazeboAug 19 2016This paper presents an extension of the OpenAI Gym for robotics using the Robot Operating System (ROS) and the Gazebo simulator. The content discusses the software architecture proposed and the results obtained by using two Reinforcement Learning techniques: ... More
A linear filter to reconstruct the ISW effect from CMB and LSS observationsSep 15 2008The extraction of a signal from some observational data sets that contain different contaminant emissions, often at a greater level than the signal itself, is a common problem in Astrophysics and Cosmology. The signal can be recovered, for instance, using ... More
The effect of hyperfine mixing in electromagnetic and semileptonic decays of doubly heavy baryonsDec 01 2010We consider the role played by hyperfine mixing in electromagnetic and semileptonic decays of doubly heavy baryons, which give rise to large corrections to the decay widths in both cases.
Can One Distinguish Tau Neutrinos from Antineutrinos in Neutral-Current Pion Production Processes?Aug 10 2006Jan 18 2007A potential way to distinguish tau-neutrinos from antineutrinos, below the tau-production threshold, but above the pion production one, is presented. It is based on the different behavior of the neutral current pion production off the nucleon, depending ... More
The role of hyperfine mixing in $b\to c$ semileptonic and electromagnetic decays of doubly-heavy baryonsOct 04 2010We analyze the effects of hyperfine mixing in $b\to c\, $ semileptonic and electromagnetic decays of doubly heavy baryons.
Neutrino induced weak pion production off the nucleonFeb 12 2008We study neutrino induced one-pion production off the nucleon in and around the Delta resonance region. Apart from the Delta-pole mechanism we include background terms required by chiral symmetry. These background terms give sizeable contributions in ... More
Stopping time convergence for processes associated with Dirichlet formsMay 27 2017Jun 29 2017Convergence is proved for solutions of Dirichlet problems in regions with many small excluded sets (holes), as the holes become smaller and more numerous. The problem is formulated in the context of Markov processes associated with general Dirichlet forms, ... More
Understanding Multi-Step Deep Reinforcement Learning: A Systematic Study of the DQN TargetJan 22 2019Feb 07 2019Multi-step methods such as Retrace($\lambda$) and $n$-step $Q$-learning have become a crucial component of modern deep reinforcement learning agents. These methods are often evaluated as a part of bigger architectures and their evaluations rarely include ... More
Global analysis of three-flavour neutrino oscillations: synergies and tensions in the determination of theta_23, delta_CP, and the mass orderingNov 13 2018We present the results of a global analysis of the neutrino oscillation data available as of fall 2018 in the framework of three massive mixed neutrinos with the goal at determining the ranges of allowed values for the six relevant parameters. We describe ... More
Extending the OpenAI Gym for robotics: a toolkit for reinforcement learning using ROS and GazeboAug 19 2016Feb 07 2017This paper presents an extension of the OpenAI Gym for robotics using the Robot Operating System (ROS) and the Gazebo simulator. The content discusses the software architecture proposed and the results obtained by using two Reinforcement Learning techniques: ... More
Event Horizon of the Monopole-Quadrupole solution: geometric and thermodynamic propertiesOct 10 2011We investigate the general geometric properties of the surface of infinite red-shift corresponding to the event horizon of the static and axisymmetric solution of the Einstein vacuum equations that only possesses mass $M$ and quadrupole moment $Q$. The ... More
Subspaces of rearrangement-invariant spacesMar 02 1995We prove a number of results concerning the embedding of a Banach lattice $X$ into an r.i. space $Y$. For example we show that if $Y$ is an r.i. space on $[0,\infty)$ which is $p$-convex for some $p>2$ and has nontrivial concavity then any Banach lattice ... More
Electromagnetic Properties of the Delta(1232)Oct 25 1996We calculate the electromagnetic moments and radii of the Delta(1232) in the nonrelativistic quark model, including two-body exchange currents. We show that two-body exchange currents lead to nonvanishing Delta and N-->Delta transition quadrupole moments ... More
Low-scale seesaw models versus $N_{\rm eff}$Nov 11 2013Nov 27 2013We consider the contribution of the extra sterile states in generic low-scale seesaw models to extra radiation, parametrized by $N_{\rm eff}$. We find that the value of $N_{\rm eff}$ is roughly independent of the seesaw scale within a wide range. We explore ... More
GIARPS: commissioning and first scientific resultsAug 09 2018GIARPS (GIAno \& haRPS) is a project devoted to have on the same focal station of the Telescopio Nazionale Galileo (TNG) both high resolution spectrographs, HARPS-N (VIS) and GIANO-B (NIR), working simultaneously. This could be considered the first and ... More
Exclusive semileptonic decays of ground-state $cb$ baryons driven by a $c\to s,d$ quark transitionJun 25 2012We evaluate semileptonic decays of spin-1/2 and spin-3/2 doubly heavy $cb$ baryons. The decays are driven by a $c\to s,d$ transition at the quark level. We check our results for the form factors against heavy quark spin symmetry constraints obtained in ... More
Weak Pion Production off the NucleonJan 18 2007Jun 19 2007We develop a model for the weak pion production off the nucleon, which besides the Delta pole mechanism (weak excitation of the $\Delta(1232)$ resonance and its subsequent decay into $N\pi$), includes also some background terms required by chiral symmetry. ... More
Study of the semileptonic decay Λ_b^0 \to Λ_c^+ l^- \barν_lAug 04 2004Within the framework of a nonrelativistic quark model we evaluate the six form factors associated to the \Lambda_b^0 \to \Lambda_c^+ l^- \bar{\nu}_l semileptonic decay. The baryon wave functions were evaluated using a variational approach applied to a ... More
Gravitational fields as generalized string modelsSep 25 2008We show that Einstein's main equations for stationary axisymmetric fields in vacuum are equivalent to the motion equations for bosonic strings moving on a special nonflat background. This new representation is based on the analysis of generalized harmonic ... More
Algebraic quotient modules and subgroup depthJun 04 2013May 25 2014In arXiv:1210.3178 it was shown that subgroup depth may be computed from the permutation module of the left or right cosets: this holds more generally for a Hopf subalgebra, from which we note in this paper that finite depth of a Hopf subalgebra R < H ... More
Spectroscopic Gradients in Elliptical GalaxiesJul 12 1995Preliminary results based on a large compilation of line-strength profiles are presented and discussed. Elliptical galaxies (Es) with strong central Mg$_2$ show steeper line-strength gradients. These galaxies are more massive and have higher velocity ... More
Superstring Vertex Operators in an AdS_5 x S^5 BackgroundSep 21 2000A quantizable action has recently been proposed for the superstring in an AdS_5 x S^5 background with Ramond-Ramond flux. In this paper, we construct physical vertex operators corresponding to on-shell fluctuations around the AdS_5 x S^5 background. The ... More
Dynamical properties of liquid lithium above meltingMar 29 1999The dynamical properties of liquid lithium at several thermodynamic states near the triple point have been studied within the framework of the mode-coupling theory. We present a self-consistent scheme which, starting from the knowledge of the static structural ... More
Convenient filtering techniques for LIGO strain of the GW150914 eventMar 01 2019We present a new strategy for the pre-processing filtering techniques of the LIGO strain of the GW150914\cite{Abbott:2016blz,TheLIGOScientific:2016wfe} event that intends to extract as much physical information as possible, minimizing the use of prior ... More
Cropping Euler factors of modular L-functionsFeb 23 2010Mar 29 2010According to the Birch and Swinnerton-Dyer conjectures, if A/Q is an abelian variety then its L-function must capture substantial part of the arithmetic properties of A. The smallest number field L where A has all its endomorphisms defined must also have ... More
Detection of variable Si II, Mn II and Fe II emission lines in the magnetic Bp star a CentauriMar 09 2007The nature of non-variable high-excitation emission lines detected in the optical spectra of normal late-B type and chemically peculiar HgMn and PGa stars is still poorly understood. To better understand the origin of the weak emission lines in B type ... More
Deep convolutional recurrent autoencoders for learning low-dimensional feature dynamics of fluid systemsAug 03 2018Aug 22 2018Model reduction of high-dimensional dynamical systems alleviates computational burdens faced in various tasks from design optimization to model predictive control. One popular model reduction approach is based on projecting the governing equations onto ... More
Phase-space structures and stellar populations in the star-forming region NGC~ 2264Nov 08 2016In this work we analyse the structure of a subspace of the phase space of the star-forming region NGC~ 2264 using the Spectrum of Kinematic Groupings (SKG). We show that the SKG can be used to process a collection of star data to find substructure at ... More
Reply to the comment by D. Kreimer and E. MielkeJun 21 1999We respond to the comment by Kreimer et. al. about the torsional contribution to the chiral anomaly in curved spacetimes. We discuss their claims and refute its main conclusion.
Cosmic implications on thermodynamics and the explanation of the so called horizon problemNov 26 1999Nov 27 1999We show that there are implications on thermodynamics that come from the existence of the initial cosmic singularity. At present time this is more a conceptual change than an observable one. However at very early cosmic times there is a big difference ... More
Two-way Communication with Adaptive Data AcquisitionSep 26 2012Motivated by computer networks and machine-to-machine communication applications, a bidirectional link is studied in which two nodes, Node 1 and Node 2, communicate to fulfill generally conflicting informational requirements. Node 2 is able to acquire ... More
Robust Coding for Lossy Computing with Receiver-Side Observation CostsAug 07 2011Apr 18 2012An encoder wishes to minimize the bit rate necessary to guarantee that a decoder is able to calculate a symbolwise function of a sequence available only at the encoder and a sequence that can be measured only at the decoder. This classical problem, first ... More
The Definition of Entropy for Quantum Unstable Systems: A View-Point Based on the Properties of Gamow StatesMar 27 2018In this paper, we review the concept of entropy in connection with the description of quantum unstable systems. We revise the conventional definition of entropy due to Boltzmann and extend it so as to include the presence of complex-energy states. After ... More
A minimal representation of the self-assembly of virus capsidsDec 16 2013Viruses are biological nanosystems with a capsid of protein-made capsomer units that encloses and protects the genetic material responsible for their replication. Here we show how the geometrical constraints of the capsomer-capsomer interaction in icosahedral ... More
Deeply Virtual Neutrino Production of $π^0$ from Nucleon and Nuclear TargetsNov 02 2009In most experiments aimed at determining the masses and mixing parameters for neutrino oscillations in different energy regimes there are strong backgrounds to neutrino interactions with matter that can confuse the expected small signals. One particular ... More
Supernova 2014J at M82: II. Direct Analysis of Spectra Obtained with Isaac Newton and William Herschel TelescopesDec 08 2015May 25 2016We analyze a time series of optical spectra of SN~2014J from almost two weeks prior to maximum to nearly four months after maximum. We perform our analysis using the SYNOW code, which is well suited to track the distribution of the ions with velocity ... More
Detectors and Concepts for sub-100 ps timing with gaseous detectorsJun 27 2016Jul 06 2016We give a short compendium of the main ongoing detectors and concepts capable of performing accurate sub-100 ps timing at high particle fluxes and on large areas, through technologies based on gaseous media. We briefly discuss the state-of-the-art, technological ... More
Complex oscillator and Painlevé IV equationMar 27 2015Supersymmetric quantum mechanics is a powerful tool for generating exactly solvable potentials departing from a given initial one. In this article the first- and second- order supersymmetric transformations will be used to obtain new exactly solvable ... More