Results for "M. H. Aguirre"

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AME - Asteroseismology Made Easy. Estimating stellar properties by use of scaled modelsApr 08 2014We present a new method to obtain stellar properties for stars exhibiting solar-like oscillations in an easy, fast, and transparent way. The method, called Asteroseismology Made Easy (AME), can determine stellar masses, mean-densities, radii, and surface ... More
Equation of state of hadronic matter with dibaryons in an effective quark modelJun 17 1998Jun 29 1998The equation of state of symmetric nuclear matter with the inclusion of non-strange dibaryons is studied. We pay special attention to the existence of a dibaryon condensate at zero temperature. These calculations have been performed in an extended quark-meson ... More
Density dependence of the MIT bag parameters from the field theory of hadronsNov 14 1996Mar 25 1997A self-consistent description of the MIT bag parameters as functions of the nuclear matter density is presented. The subnuclear degrees of freedom are treated in the Quark-Meson Coupling Model, considering the equilibrium conditions for the bag in the ... More
EMC effect from the QMC and the QHD descriptionsApr 09 1997Sep 15 1997The density dependence of the bag parameters is studied in a framework which links the Quark-Meson Coupling model and the field theory of hadrons for nuclear matter description. The EMC effect is treated in the dynamical rescaling hypothesis by using ... More
Low-mass disc galaxies and the issue of stability: MOND vs dark matterAug 22 2016We analyse the rotation curves and gravitational stability of a sample of six bulgeless galaxies for which detailed images reveal no evidence for strong bars. We explore two scenarios: Newtonian dark matter models and MOdified Newtonian Dynamics (MOND). ... More
Electron degeneracy and intrinsic magnetic properties of epitaxial Nb:SrTiO$_3$ thin-films controlled by defectsApr 14 2015Sep 24 2015We report thermoelectric power experiments in e-doped thin films of SrTiO$_3$ (STO) which demonstrate that the electronic band degeneracy can be lifted through defect management during growth. We show that even small amounts of cationic vacancies, combined ... More
"Parallel Training Considered Harmful?": Comparing series-parallel and parallel feedforward network trainingJun 21 2017Aug 14 2018Neural network models for dynamic systems can be trained either in parallel or in series-parallel configurations. Influenced by early arguments, several papers justify the choice of series-parallel rather than parallel configuration claiming it has a ... More
Schemata as Building Blocks: Does Size Matter?Jun 30 2000We analyze the schema theorem and the building block hypothesis using a recently derived, exact schemata evolution equation. We derive a new schema theorem based on the concept of effective fitness showing that schemata of higher than average effective ... More
ACCRETION OF HOT DARK MATTER ONTO SLOWLY MOVING COSMIC STRINGSMay 05 1995Cosmic strings with small-scale structure have a coarse-grained mass per unit length $\mu$ which is larger than the string tension. This leads to an effective Newtonian gravitational line source and to a characteristic translational velocity which is ... More
Lasso Regularization Paths for NARMAX Models via Coordinate DescentOct 02 2017Feb 26 2018We propose a new algorithm for estimating NARMAX models with $L_1$ regularization for models represented as a linear combination of basis functions. Due to the $L_1$-norm penalty the Lasso estimation tends to produce some coefficients that are exactly ... More
Seismic measurement of the locations of the base of convection zone and helium ionization zone for stars in the {\it Kepler} seismic LEGACY sampleJan 31 2017Acoustic glitches are regions inside a star where the sound speed or its derivatives change abruptly. These leave a small characteristic oscillatory signature in the stellar oscillation frequencies. With the precision achieved by {\it Kepler} seismic ... More
Neutron star structure in a quark model with excluded volume correctionNov 12 2002Sep 30 2003We study the effects of the finite size of baryons on the equation of state of homogeneous hadronic matter. The finite extension of hadrons is introduced in order to improve the performance of field theoretical models at very high densities. We simulate ... More
Quantum coarse-grained entropy and thermodynamicsJul 31 2017Jan 15 2019We extend classical coarse-grained entropy, commonly used in many branches of physics, to the quantum realm. We find two coarse-grainings, one using measurements of local particle numbers and then total energy, and the second using local energy measurements, ... More
Anything can happen, but only given half a chance: a quantum bound on large fluctuations away from equilibriumJun 23 2018We ask to what extent an isolated quantum system can eventually "contract" to be contained within a given Hilbert subspace. We do this by starting with an initial random state, considering the probability that all the particles will be measured in a fixed ... More
Landau parameters for isospin asymmetric nuclear matter based on a relativistic model of composite and finite extension nucleonsNov 01 2006Nov 02 2006We study the properties of cold asymmetric nuclear matter at high density, applying the quark meson coupling model with excluded volume corrections in the framework of the Landau theory of relativistic Fermi liquids. We discuss the role of the finite ... More
Collective modes in strange and isospin asymmetric hadronic matterMar 25 2004Mar 09 2005We study the propagation of non-strange and strange meson modes in hadronic matter considering both isospin and strangeness mixings induced by quantum fluctuations in the medium. Baryons are described using the Quark Meson Coupling model extended to include ... More
Asteroseismic age determination for dwarfs and giantsDec 07 2015Asteroseismology can make a substantial contribution to our understanding of the formation history and evolution of our Galaxy by providing precisely determined stellar properties for thousands of stars in different regions of the Milky Way. We present ... More
The Spatial Distribution of Metals in the Intergalactic MediumJul 04 2005Oct 11 2005We investigate the impact of environment on the metallicity of the diffuse intergalactic medium. We use pixel correlation techniques to search for weak CIV and OVI absorption in the spectrum of quasar Q1422+231 in regions of the spectrum close to and ... More
Successful strategies for competing networksMar 01 2013Jul 02 2013Competitive interactions represent one of the driving forces behind evolution and natural selection in biological and sociological systems. For example, animals in an ecosystem may vie for food or mates; in a market economy, firms may compete over the ... More
Regulating Eternal Inflation II: The Great DivideMar 14 2006In a previous paper, two of the authors presented a "regulated" picture of eternal inflation. This picture both suggested and drew support from a conjectured discontinuity in the amplitude for tunneling from positive to negative vacuum energy, as the ... More
Classical dynamical coarse-grained entropy and comparison with the quantum versionMay 09 2019We introduce the framework of classical Observational entropy, which is a mathematically rigorous and precise framework for non-equilibrium thermodynamics, explicitly defined in terms of a set of observables. Observational entropy can be seen as a generalization ... More
Suspension flow: do particles act as mixers?Mar 16 2015Recently, Roht et al. [J. Contam. Hydrol. 145, 10-16 (2013)] observed that the presence of suspended non-Brownian macroscopic particles decreased the dispersivity of a passive solute, for a pressure-driven flow in a narrow parallel-plates channel at low ... More
In-medium covariant propagator of baryons under a strong magnetic field: effect of the intrinsic magnetic momentsApr 12 2016Oct 27 2016We obtain the covariant propagator at finite temperature for interacting baryons immersed in a strong magnetic field. The effect of the intrinsic magnetic moments on the Green function are fully taken into account. We make an expansion in terms of eigenfunctions ... More
Finite temperature collective modes in a two phase coexistence region of asymmetric nuclear matterSep 04 2010Oct 18 2010The relation between collective modes and the phase transition in low density nuclear matter is examined. The dispersion relations for collective modes in a linear approach are evaluated within a Landau-Fermi liquid scheme by assuming coexisting phases ... More
Equation of State of Hypermatter in beta Equilibrium in a Quark Model with Excluded Volume CorrectionJul 21 1999We study the effects of the finite size of the baryons on the equation of state of homogeneous hadronic matter with hyperons. The finite extension of hadrons is introduced in order to improve the perfomance of field theoretical models at very high densities, ... More
Quantum coarse-grained entropy and thermalization in closed systemsMar 02 2018Jan 15 2019We investigate the detailed properties of Observational entropy, introduced by \v{S}afr\'{a}nek et al. [Phys. Rev. A 99, 010101 (2019)] as a generalization of Boltzmann entropy to quantum mechanics. This quantity can involve multiple coarse-grainings, ... More
Development of Aluminum LEKIDs for Balloon-Borne Far-IR SpectroscopyMar 06 2018Apr 16 2018We are developing lumped-element kinetic inductance detectors (LEKIDs) designed to achieve background-limited sensitivity for far-infrared (FIR) spectroscopy on a stratospheric balloon. The Spectroscopic Terahertz Airborne Receiver for Far-InfraRed Exploration ... More
Observation of the spin Seebeck effect in epitaxial Fe3O4 thin filmsDec 13 2012We report the first experimental observation of the spin Seebeck effect in magnetite thin films. The signal observed at temperatures above the Verwey transition is a contribution from both the anomalous Nernst (ANE) and spin Seebeck effects (SSE). The ... More
Interface-induced anomalous Nernst effect in Fe3O4/Pt-based heterostructuresSep 28 2018We have studied the anomalous Nernst effect (ANE) in [Fe3O4/Pt]-based heterostructures, by measuring the ANE-induced electric field with a magnetic field applied normal to the sample surface, in the perpendicular magnetized configuration, where only the ... More
Giant Memcapacitance in Topotactic Redox InterfacesMay 14 2019The possibility to develop neuromorphic computing devices able to mimic the extraordinary data processing capabilities of biological systems spurs the research on memristive systems. Memristors with additional functionalities such as robust memcapacitance ... More
Electron swaps and the stopping of protons by hydrogenAug 20 2009The relevance of the electronic swap in the stopping process of proton by hydrogen is investigated. To this end, the Classical Trajectory Monte-Carlo method is used to calculate the k-stopping cross-section, i.e. the stopping cross-section given the occurrence ... More
The Bolocam 1.1 mm Lockman Hole Galaxy Survey: SHARC II 350 micron Photometry and Implications for Spectral Models, Dust Temperatures, and Redshift EstimationJan 25 2006Feb 25 2006We present 350 micron photometry of all 17 galaxy candidates in the Lockman Hole detected in a 1.1 mm Bolocam survey. Several of the galaxies were previously detected at 850 microns, at 1.2 mm, in the infrared by Spitzer, and in the radio. Nine of the ... More
Thermoelectric performance of spin Seebeck effect in Fe3O4/Pt-based thin film heterostructuresMay 12 2016We report a systematic study on the thermoelectric performance of spin Seebeck devices based on Fe3O4/Pt junction systems. We explore two types of device geometries: a spin Hall thermopile and spin Seebeck multilayer structures. The spin Hall thermopile ... More
Pure double-layer bubbles in quadratic F(R) gravityApr 03 2017Jun 02 2017We present a class of spherically symmetric spacetimes corresponding to bubbles separating two regions with constant values of the scalar curvature, or equivalently with two different cosmological constants, in quadratic F(R) theory. The bubbles are obtained ... More
Observations of M87 and Hydra A at 90 GHzFeb 18 2009This paper presents new observations of the AGNs M87 and Hydra A at 90 GHz made with the MUSTANG bolometer array on the Green Bank Telescope at 8.5" resolution. A spectral analysis is performed combining this new data and archival VLA data on these objects ... More
Out of equilibrium: understanding cosmological evolution to lower-entropy statesAug 01 2011Despite the importance of the Second Law of Thermodynamics, it is not absolute. Statistical mechanics implies that, given sufficient time, systems near equilibrium will spontaneously fluctuate into lower-entropy states, locally reversing the thermodynamic ... More
Constraining mixing processes in stellar cores using asteroseismology. Impact of semiconvection in low-mass starsFeb 03 2011The overall evolution of low-mass stars is heavily influenced by the processes occurring in the stellar interior. In particular, mixing processes in convectively unstable zones and overshooting regions affect the resulting observables and main sequence ... More
The Dense Molecular Gas in the Circumnuclear Disk of NGC 1068Feb 18 2011We present a 190-307 GHz broadband spectrum obtained with Z-Spec of NGC 1068 with new measurements of molecular rotational transitions. After combining our measurements with those previously published and considering the specific geometry of this Seyfert ... More
A Census of the High-Density Molecular Gas in M82Jun 10 2010Aug 26 2010We present a three-pointing study of the molecular gas in the starburst nucleus of M82 based on 190 - 307 GHz spectra obtained with Z-Spec at the Caltech Submillimeter Observatory. We present intensity measurements, detections and upper limits, for 20 ... More
The Warm Molecular Gas Around the Cloverleaf QuasarAug 13 2009Sep 08 2009We present the first broadband lambda = 1 mm spectrum toward the z=2.56 Cloverleaf Quasar, obtained with Z-Spec, a 1-mm grating spectrograph on the 10.4-meter Caltech Submillimeter Observatory. The 190-305 GHz observation band corresponds to rest-frame ... More
Observation of huge thermal spin currents in magnetic multilayersMar 18 2015Thermal spin pumping constitutes a novel mechanism for generation of spin currents; however their weak intensity constitutes a major roadblock for its usefulness. We report a phenomenon that produces a huge spin current in the central region of a multilayer ... More
Nuclear matter superfluidity in an effective hadronic field model with excluded volume correctionsMar 05 2013Properties of the 1S0 superfluid phase are studied for symmetric nuclear matter at finite temperature. It is described within a covariant hadronic field model, of the sigma-omega type, with addition of density dependent correlations simulating effects ... More
Eternal Inflation, past and futureDec 04 2007Cosmological inflation, if it occurred, radically alters the picture of the `big bang', which would merely point to reheating at the end of inflation. Moreover, this reheating may be only local, so that inflation continues elsewhere and forever, continually ... More
Alternatives to Dark Matter (?)Oct 20 2003Oct 22 2003It has long been known that Newtonian dynamics applied to the visible matter in galaxies and clusters does not correctly describe the dynamics of those systems. While this is generally taken as evidence for dark matter it is in principle possible that ... More
Hadronic matter under an external magnetic field: in medium modification of the pion massDec 01 2016The covariant propagator of a fermion with anomalous magnetic moment interacting with an uniform external magnetic field at finite temperature and baryonic density is presented . The case of a scalar boson is also considered. The final expressions are ... More
High Spectral Resolution Measurement of the Sunyaev-Zel'dovich Effect Null with Z-SpecJan 31 2012Aug 05 2013The Sunyaev-Zel'dovich (SZ) effect spectrum crosses through a null where dT_CMB = 0 near nu_0 = 217 GHz. In a cluster of galaxies, nu_0 can be shifted from the canonical thermal SZ effect value by corrections to the SZ effect scattering due to the properties ... More
The Water Vapor Spectrum of APM 08279+5255: X-Ray Heating and Infrared Pumping over Hundreds of ParsecsJun 21 2011Jul 18 2011We present the rest-frame 200--320 \mm\ spectrum of the z=3.91 quasar \apm, obtained with Z-Spec at the Caltech Submillimeter Observatory. In addition to the \jeight\ to \jthirteen\ CO rotational transitions which dominate the CO cooling, we find six ... More
N=1 super sinh-Gordon model in the half line: Breather solutionsApr 16 2013We examine the N=1 super sinh-Gordon (SShG) model restricted into the half line through a reduction from the defect SShG model. The B\"acklund transformations are employed to generate one-, two- and three-soliton solutions as well as a class of breathers ... More
Grassmanian and Bosonic Thirring Models with Jump DefectsDec 07 2010In this paper we discuss the Lax formulation of the Grassmanian and Bosonic Thirring models in the presence of jump defects. For the Grassmanian case, the defect is described by B\"acklund transformation which is responsible for preserving the integrability ... More
Thirring Model with Jump DefectOct 15 2009Oct 28 2009The purpose of our work is to extend the formulation of classical affine Toda Models in the presence of jump defects to pure fermionic Thirring model. As a first attempt we construct the Lagrangian of the Grassmanian Thirring model with jump defect (of ... More
Nuclear superfluidity in isospin asymmetric matter within the Skyrme modelJun 13 2013The phase diagram of the superfluid phase coupled to spin singlet (S=0) and isospin triplet (T=1) states in infinite nuclear matter is analyzed within the nonrelativistic Skyrme model. We use an approach that allows a unified and consistent treatment ... More
Representations in Density Dependent Hadronic Field Theory and compatibility with QCD sum-rulesAug 25 2005Different representations of an effective, covariant theory of the hadronic interaction are examined. For this purpose we have introduced nucleon-meson vertices parametrized in terms of scalar combinations of hadronic fields, extending the conceptual ... More
Compatibility of QCD sum-rules and Hadron field theory in a dense mediumNov 24 2004The compatibility of the QCD sum rules and effective hadronic models predictions are examined. For this purpose we have considered the results for the nucleon self-energy in a dense hadronic environment provided by two independent QCD sum-rules calculations. ... More
Chiral symmetry and strangeness content in nuclear physics parametrized by a medium dependent bag constantDec 04 2002Mar 07 2003Non-perturbative QCD vacuum effects at finite density are parametrized by means of a bag constant $B$. It is extracted from a Nambu- Jona Lasinio model with two or three flavors. The parameter $B$ is used in an effective quark-meson coupling model to ... More
On making predictions in a multiverse: conundrums, dangers, and coincidencesJun 22 2005The notion that there are many "universes" with different properties is one answer to the question of "why is the universe so hospitable to life?" This notion also naturally follows from current ideas in eternal inflation and string/M theory. But how ... More
Finitary Process Evolution I: Information Geometry of Configuration Space and the Process-Replicator DynamicsJul 12 2018Jul 25 2018This report presents some fundamental mathematical results towards elucidating the information-geometric underpinnings of evolutionary modelling schemes for (quasi-)stationary discrete stochastic processes. The model class under consideration is that ... More
Interferometric diameters of five evolved intermediate-mass planet-hosting stars measured with PAVO at the CHARA ArrayApr 16 2018Debate over the planet occurrence rates around intermediate-mass stars has hinged on the accurate determination of masses of evolved stars, and has been exacerbated by a paucity of reliable, directly-measured fundamental properties for these stars. We ... More
The sinh-Gordon defect matrix generalized for n defectsOct 06 2016In this paper we obtain a general expression for the n-defect matrix for the sinh-Gordon model. This in turn generate the general B\"acklund transformations (BT) for a system with $n$ type-I defects, through a gauge transformation.
Tuning the Interfacial Charge, Orbital and Spin Polarization Properties in La0.67Sr0.33MnO3/ La1-xSrxMnO3 BilayersDec 10 2017The possibility of controlling the interfacial properties of artificial oxide heterostructures is still attracting researchers in the field of materials engineering. Here, we used surface sensitive techniques and high-resolution transmission electron ... More
The Cold Big-Bang Cosmology as a Counter-example to Several Anthropic ArgumentsJun 07 2001Jul 12 2001A general Friedmann big-bang cosmology can be specified by fixing a half-dozen cosmological parameters such as the photon-to-baryon ratio Eta, the cosmological constant Lambda, the curvature scale R, and the amplitude Q of (assumed scale-invariant) primordial ... More
Confirming chemical clocks: asteroseismic age dissection of the Milky Way disk(s)Oct 26 2017Jan 15 2018Investigations of the origin and evolution of the Milky Way disk have long relied on chemical and kinematic identification of its components to reconstruct our Galactic past. Difficulties in determining precise stellar ages have restricted most studies ... More
Defects in the supersymmetric mKdV hierarchy via Backlund transformationsSep 16 2017Jan 05 2018The integrability of the ${\cal N}=1$ supersymmetric modified Korteweg de-Vries (smKdV) hierarchy in the presence of defects is investigated through the construction of its super B\"acklund transformation. The construction of such transformation is performed ... More
Type-II super-Backlund transformation and integrable defects for the N=1 super sinh-Gordon modelApr 29 2015Jun 25 2015A new super-Backlund transformation for the N=1 supersymmetric sinh-Gordon equation is constructed. Based on this construction we propose a type-II integrable defect for the supersymmetric sinh-Gordon model consistent with this new transformation through ... More
Type-II Bäcklund Transformations via Gauge TransformationsOct 07 2011Dec 19 2011The construction of type II Backlund transformation for the sine-Gordon and the Tzitzeica-Bullough-Dodd models are obtained from gauge transformation. An infinite number of conserved quantities are constructed from the defect matrices. This guarantees ... More
The Spectrum of Integrated Millimeter Flux of the Magellanic Clouds and 30-Doradus from TopHat and DIRBE DataJun 20 2003We present measurements of the integrated flux relative to the local background of the Large and Small Magellanic Clouds and the region 30-Doradus (the Tarantula Nebula) in the LMC in four frequency bands centered at 245, 400, 460, and 630 GHz, based ... More
An alternative construction for the Type-II defect matrix for sshGOct 06 2016In this paper we construct a Type-II defect (super) matrix for the supersymmetric sinh-Gordon model as a product of two Type-I defect (super) matrices. We also show that the resulting defect matrix corresponds to a fused defect.
Recursion Operator and Bäcklund Transformation for Super mKdV HierarchyApr 17 2018In this paper we consider the ${\cal N}=1$ supersymmetric mKdV hierarchy composed of positive odd flows embedded within an affine $\hat sl(2,1)$ algebra. Its B\"acklund transformations are constructed in terms of a gauge transformation preserving the ... More
Fusing defect for the N=2 super sinh-Gordon modelFeb 01 2016In this paper we derive the type-II integrable defect for the N = 2 supersymmetric sinh-Gordon (sshG) model by using the fusing procedure. In particular, we show explicitly the conservation of the modified energy, momentum and supercharges.
Stellar models with calibrated convection and temperature stratification from 3D hydrodynamics simulationsMay 31 2018Stellar evolution codes play a major role in present-day astrophysics, yet they share common simplifications related to the outer layers of stars. We seek to improve on this by the use of results from realistic and highly detailed 3D hydrodynamics simulations ... More
On the Smoothness of Nonlinear System IdentificationMay 02 2019New light is shed onto optimization problems resulting from prediction error parameter estimation of linear and nonlinear systems. It is shown that the smoothness" of the objective function depends both on the simulation length and on the decay rate of ... More
Testing Asteroseismic Radii of Dwarfs and Subgiants with Kepler and GaiaFeb 04 2018We test asteroseismic radii of Kepler main-sequence and subgiant stars by deriving their parallaxes which are compared with those of the first Gaia data release. We compute radii based on the asteroseismic scaling relations as well as by fitting observed ... More
Real-time resilient focusing through a bending multimode fiberMar 08 2013We introduce a system capable of focusing light through a multimode fiber in 37ms, one order of magnitude faster than demonstrated in previous reports. As a result, the focus spot can be maintained during significant bending of the fiber, opening numerous ... More
Stellar Evolution and Variability in the Pre-ZAHB PhaseJul 18 2008One of the most dramatic events in the life of a low-mass star is the He flash, which takes place at the tip of the RGB and is followed by a series of secondary flashes before the star settles on the zero-age HB (ZAHB). Yet, no stars have ever been positively ... More
Generation of maximally entangled states of qudits using twin photonsNov 08 2004We report an experiment to generate maximally entangled states of D-dimensional quantum systems, qudits, by using transverse spatial correlations of two parametric down-converted photons. Apertures with D-slits in the arms of the twin fotons define the ... More
Metal Enrichment of the Intergalactic Medium in Cosmological SimulationsMay 03 2001Jul 17 2001Observations have established that the diffuse intergalactic medium (IGM) at z ~ 3 is enriched to ~0.1-1% solar metallicity and that the hot gas in large clusters of galaxies (ICM) is enriched to 1/3-1/2 solar metallicity at z=0. Metals in the IGM may ... More
N=1 super sinh-Gordon model with defects revisitedDec 08 2014The Lax pair formalism is considered to discuss the integrability of the N=1 supersymmetric sinh-Gordon model with a defect. We derive associated defect matrix for the model and construct the generating functions of the modified conserved quantities. ... More
Terahertz spin currents and inverse spin Hall effect in thin-film heterostructures containing complex magnetic compoundsMay 31 2017Terahertz emission spectroscopy of ultrathin multilayers of magnetic and heavy metals has recently attracted much interest. This method not only provides fundamental insights into photoinduced spin transport and spin-orbit interaction at highest frequencies ... More
Energy Dissipation and Trapping of Particles Moving on a Rough SurfaceAug 19 1997We report an experimental, numerical and theoretical study of the motion of a ball on a rough inclined surface. The control parameters are $D$, the diameter of the ball, $\theta$, the inclination angle of the rough surface and $E_{ki}$, the initial kinetic ... More
Hybrid photoacoustic/fluorescence microendoscopy through a multimode fiber using speckle illuminationDec 28 2018We present an ultra-thin hybrid imaging system based on an optical multimode fiber (MMF) and an optical fiber hydrophone that combines optical resolution photoacoustic and fluorescence microscopy. To control the illumination at the distal tip of the MMF, ... More
The absorbers towards Q0836+113Oct 18 1996We have performed RIJHK_S imaging of the field around the z=2.67 quasar Q0836+113, which presents several metal line and a damped Ly\alpha absorption systems in its spectrum. The images reveal the existence of a red K_S=18.9 object \approx 11 arcsec from ... More
Super-poissonian photon statistics and correlations between pump and probe fields in Electromagnetically Induced TransparencyApr 11 2002We have measured the photon statistics of pump and probe beams after interaction with Rb atoms in a situation of Electromagnetically Induced Transparency. Both fields present super-poissonian statistics and their intensities become correlated, in good ... More
Synchronization of interconnected networks: the role of connector nodesMay 31 2014Jun 04 2014In this Letter we identify the general rules that determine the synchronization properties of interconnected networks. We study analytically, numerically and experimentally how the degree of the nodes through which two networks are connected influences ... More
The enrichment history of cosmic metalsMay 21 2010Jul 06 2010We use a suite of cosmological, hydrodynamical simulations to investigate the chemical enrichment history of the Universe. Specifically, we trace the origin of the metals back in time to investigate when various gas phases were enriched and by what halo ... More
Measuring Galaxy Clustering and the Evolution of [CII] Mean Intensity with far-IR Line Intensity Mapping During 0.5 < z < 1.5Jul 18 2014Infrared fine-structure emission lines from trace metals are powerful diagnostics of the interstellar medium in galaxies. We explore the possibility of studying the redshifted far-IR fine-structure line emission using the three-dimensional (3-D) power ... More
SpaceInn hare-and-hounds exercise: Estimation of stellar properties using space-based asteroseismic dataApr 28 2016Context: Detailed oscillation spectra comprising individual frequencies for numerous solar-type stars and red giants are or will become available. These data can lead to a precise characterisation of stars. Aims: Our goal is to test and compare different ... More
Pulsation Period Changes as a Tool to Identify Pre-Zero Age Horizontal Branch StarsDec 08 2009One of the most dramatic events in the life of a low-mass star is the He flash, which takes place at the tip of the red giant branch (RGB) and is followed by a series of secondary flashes before the star settles into the zero-age horizontal branch (ZAHB). ... More
ALMA observations of atomic carbon in z~4 dusty star-forming galaxiesDec 13 2016We present ALMA [CI]($1-0$) (rest frequency 492 GHz) observations for a sample of 13 strongly-lensed dusty star-forming galaxies originally discovered at 1.4mm in a blank-field survey by the South Pole Telescope. We compare these new data with available ... More
The Asteroseismic Target List (ATL) for solar-like oscillators observed in 2-minute cadence with the Transiting Exoplanet Survey Satellite (TESS)Jan 29 2019We present the target list of solar-type stars to be observed in short-cadence (2-min) for asteroseismology by the NASA Transiting Exoplanet Survey Satellite (TESS) during its 2-year nominal survey mission. The solar-like Asteroseismic Target List (ATL) ... More
Standing on the shoulders of Dwarfs: the Kepler asteroseismic LEGACY sample II - radii, masses, and agesNov 27 2016We use asteroseismic data from the Kepler satellite to determine fundamental stellar properties of the 66 main-sequence targets observed for at least one full year by the mission. We distributed tens of individual oscillation frequencies extracted from ... More
Beyond the Kepler/K2 bright limit: variability in the seven brightest members of the PleiadesAug 24 2017The most powerful tests of stellar models come from the brightest stars in the sky, for which complementary techniques, such as astrometry, asteroseismology, spectroscopy, and interferometry can be combined. The K2 Mission is providing a unique opportunity ... More
Implications of a High Angular Resolution Image of the Sunyaev-Zel'dovich Effect in RXJ1347-1145Oct 27 2009May 10 2010The most X-ray luminous cluster known, RXJ1347-1145 (z=0.45), has been the object of extensive study across the electromagnetic spectrum. We have imaged the Sunyaev-Zel'dovich Effect (SZE) at 90 GHz (3.3 mm) in RXJ1347-1145 at 10" resolution with the ... More
Oscillation mode linewidths of main-sequence and subgiant stars observed by KeplerDec 14 2011Solar-like oscillations have been observed by {{\it Kepler}} and CoRoT in several solar-type stars. We study the variations of stellar p-mode linewidth as a function of effective temperature. Time series of 9 months of Kepler data have been used. The ... More
Quantum Instability of the Emergent UniverseJun 13 2013Nov 19 2013We perform a semi-classical analysis of the Emergent Universe scenario for inflation. Fixing the background, and taking the inflaton to be homogenous, we cast the inflaton's evolution as a one-dimensional quantum mechanics problem. We find that the tuning ... More
Dust Versus Cosmic AccelerationNov 19 1998Dec 17 1998Two groups have recently discovered a statistically significant deviation in the fluxes of high-redshift type Ia supernovae from the predictions of a Friedmann model with zero cosmological constant. In this Letter, I argue that bright, dusty, starburst ... More
How Did the IGM Become Enriched?Nov 20 2006The enrichment of the intergalactic medium with heavy elements is a process that lies at the nexus of poorly-understood aspects of physical cosmology. We review current understanding of the processes that may remove metals from galaxies, the basic predictions ... More
Generalised Stability of ultraproducts of finite residue ringsMar 15 2015We study ultraproducts of finite residue rings $\underset{n\in\mathbb{N}}{\prod}\mathbb{Z}/n\mathbb{Z} \diagup \mathcal{U} $ where $\mathcal{U}$ is a non-principal ultrafilter. We find sufficient conditions of the ultrafilter $\mathcal{U}$ to determine ... More
Stellar evolution and modelling starsNov 13 2017In this chapter I give an overall description of the structure and evolution of stars of different masses, and review the main ingredients included in state-of-the-art calculations aiming at reproducing observational features. I give particular emphasis ... More
The Globular Cluster NGC 5286. II. Variable StarsNov 09 2009We present the results of a search for variable stars in the globular cluster NGC 5286, which has recently been suggested to be associated with the Canis Major dwarf spheroidal galaxy. 57 variable stars were detected, only 19 of which had previously been ... More
Standing on the shoulders of Dwarfs: the Kepler asteroseismic LEGACY sample II - radii, masses, and agesNov 27 2016Nov 29 2016We use asteroseismic data from the Kepler satellite to determine fundamental stellar properties of the 66 main-sequence targets observed for at least one full year by the mission. We distributed tens of individual oscillation frequencies extracted from ... More
Measurement of acoustic glitches in solar-type stars from oscillation frequencies observed by KeplerDec 17 2013For the very best and brightest asteroseismic solar-type targets observed by Kepler, the frequency precision is sufficient to determine the acoustic depths of the surface convective layer and the helium ionization zone. Such sharp features inside the ... More