Results for "Saida M. Caballero-Nieves"

total 175031took 0.29s
Massive, wide binaries as tracers of massive star formationFeb 13 2018Massive stars can be found in wide (hundreds to thousands AU) binaries with other massive stars. We use $N$-body simulations to show that any bound cluster should always have approximately one massive wide binary: one will probably form if none are present ... More
A High Angular Resolution Survey of Massive Stars in Cygnus OB2: Results from the Hubble Space Telescope Fine Guidance SensorsNov 20 2013We present results of a high angular resolution survey of massive OB stars in the Cygnus OB2 association that we conducted with the Fine Guidance Sensor 1R (FGS1r) on the Hubble Space Telescope. FGS1r is able to resolve binary systems with a magnitude ... More
Black hole radiation with high frequency dispersionMay 11 1999Aug 24 1999We consider one model of a black hole radiation, in which the equation of motion of a matter field is modified to cut off high frequency modes. The spectrum in the model has already been analytically derived in low frequency range, which has resulted ... More
Resolved Dust Emission in a Quasar at z=3.65May 15 2009We present submillimetre observations of the z=3.653 quasar SDSS160705+533558 together with data in the optical and infrared. The object is unusually bright in the far-IR and submm with an IR luminosity of ~10^14 L_sun. We ascribe this luminosity to a ... More
A dual rigidity of the sphere and the hyperbolic planeMay 20 2015There are several well-known characterizations of the sphere as a regular surface in the Euclidean space. By means of a purely synthetic technique, we get a rigidity result for the sphere without any curvature conditions, nor completeness or compactness. ... More
The Multiplicity of Massive Stars: A High Angular Resolution Survey with the HST Fine Guidance SensorSep 30 2014We present the results of an all-sky survey made with the Fine Guidance Sensor on Hubble Space Telescope to search for angularly resolved binary systems among the massive stars. The sample of 224 stars is comprised mainly of Galactic O- and B-type stars ... More
The R136 star cluster dissected with Hubble Space Telescope/STIS. I. Far-ultraviolet spectroscopic census and the origin of HeII 1640 in young star clustersMar 16 2016We introduce a HST/STIS stellar census of R136a, the central ionizing star cluster of 30 Doradus. We present low resolution far-ultraviolet STIS/MAMA spectroscopy of R136 using 17 contiguous 52x0.2 arcsec slits which together provide complete coverage ... More
A Short Proof of a Concrete SumApr 12 2016We give an alternative proof of a formula that generalizes Hermite's identity. Instead involving modular arithmetic, our short proof relies on the Fourier-type expansion for the floor function and on a trigonometric formula.
The nucleon axial mass and the MiniBooNE Quasielastic Neutrino-Nucleus Scattering problemJun 27 2011Dec 02 2011The charged-current double differential neutrino cross section, measured by the MiniBooNE Collaboration, has been analyzed using a microscopical model that accounts for, among other nuclear effects, long range nuclear (RPA) correlations and multinucleon ... More
Shear Viscosity of the outer crust of Neutron stars: Ion ContributionJul 28 2008Oct 30 2008The shear viscosity of the crust might have a damping effect on the amplitude of r-modes of rotating neutron stars. This damping has implications for the emission of gravitational waves. We calculate the contribution to the shear viscosity coming from ... More
Explicit identities for Lévy processes associated to symmetric stable processesNov 03 2009In this paper we introduce a new class of L\'evy processes which we call hypergeometric-stable L\'evy processes, because they are obtained from symmetric stable processes through several transformations and where the Gauss hypergeometric function plays ... More
The simultaneous discharge of liquid and grains from a siloJan 17 2018The flow rate of water through an orifice at the bottom of a container depends on the hydrostatic pressure whereas for a dry granular material is nearly constant. But what happens during the simultaneous discharge of grains and liquid from a silo? By ... More
Identification of blue high proper motion objects in the Tycho-2 and 2MASS catalogues using Virtual Observatory toolsSep 17 2010May 23 2011With available Virtual Observatory tools, we looked for new bright blue high proper motion objects in the entire sky: white dwarfs, hot subdwarfs, runaway OB stars, and early-type stars in nearby young moving groups. We performed an all-sky cross-match ... More
On the Lamperti stable processesFeb 06 2008Mar 06 2008We consider a new family of $\R^d$-valued L\'{e}vy processes that we call Lamperti stable. One of the advantages of this class is that the law of many related functionals can be computed explicitely (see for instance \cite{cc}, \cite{ckp}, \cite{kp} and ... More
Impact of single-particle compressibility on the fluid-solid phase transition for ionic microgel suspensionsOct 17 2014We study ionic microgel suspensions composed of swollen particles for various single-particle stiffnesses. We measure the osmotic pressure $\pi$ of these suspensions and show that it is dominated by the contribution of free ions in solution. As this ionic ... More
Charged kaon production by coherent scattering of neutrinos and antineutrinos on nucleiMay 22 2012With the aim of achieving a better and more complete understanding of neutrino interactions with nuclear targets, the coherent production of charged kaons induced by neutrinos and antineutrinos is investigated in the energy range of some of the current ... More
Analysis of Meson Exchange and Isobar Currents in (e,e'p) Reactions from O-16Apr 12 1999Apr 13 1999An analysis of the effects of meson exchange and isobar currents in exclusive (e,e'p) processes from O-16 under quasi-free kinematics is presented. A model that has probed its feasibility for inclusive quasi-elastic (e,e') processes is considered. Sensitivity ... More
Gate induced enhancement of spin-orbit coupling in dilute fluorinated grapheneMar 04 2015We analyze the origin of spin-orbit coupling (SOC) in fluorinated graphene using Density Functional Theory (DFT) and a tight-binding model for the relevant orbitals. As it turns out, the dominant source of SOC is the atomic spin-orbit of fluorine adatoms ... More
Neutrino-nucleus CCQE-like scatteringNov 28 2014RPA correlations, spectral function and 2p2h (multi-nucleon) effects on charged-current neutrino-nucleus reactions without emitted pions are discussed. We pay attention to the influence of RPA and multi-nucleon mechanisms on the MiniBooNE and MINERvA ... More
CCQE, 2p2h excitations and ν-energy reconstructionApr 03 2013We analyze the MiniBooNE muon neutrino CCQE-like d\sigma/dT_\mu/dcos\theta_\mu data using a theoretical model that, among other nuclear effects, includes RPA correlations and 2p2h (multinucleon) mechanisms. These corrections turn out to be essential for ... More
Maximum mass of a barotropic spherical starMar 05 2015Oct 01 2015The ratio of total mass $M$ to surface radius $R$ of spherical perfect fluid ball has an upper bound, $M/R < B$. Buchdahl obtained $B = 4/9$ under the assumptions; non-increasing mass density in outward direction, and barotropic equation of states. Barraco ... More
Neutrino-induced one-pion production revisited: the $ν_μn\toμ^- nπ^+$ channelDec 07 2016We reanalyze our previous studies of neutrino-induced one-pion production on nucleons for outgoing $\pi N$ invariant masses below 1.4 GeV. Our motivation is to get a better description of the $\nu_\mu n\to\mu^- n\pi^+$ cross section, for which current ... More
Scaling Function and Nucleon Momentum DistributionApr 23 2010Scaling studies of inclusive quasielastic electron scattering reactions have been used in the past as a basic tool to obtain information on the nucleon momentum distribution in nuclei. However, the connection between the scaling function, extracted from ... More
Heavy Hadrons in Dense MatterSep 01 2015We study the behavior of dynamically-generated baryon resonances with heavy-quark content within a unitarized coupled-channel theory in matter that fulfills heavy-quark spin symmetry constraints. We analyze the implications for the formation of charmed ... More
Topical Issue in Solar Physics: Flux-rope Structure of Coronal Mass Ejections PrefaceMar 30 2013This Topical Issue of Solar Physics, devoted to the study of flux-rope structure in coronal mass ejections (CMEs), is based on two Coordinated Data Analysis Workshops (CDAWs) held in 2010 (20 - 23 September in Dan Diego, California, USA) and 2011 (September ... More
Search for bright nearby M dwarfs with Virtual Observatory toolsAug 07 2014Using Virtual Observatory tools, we cross-matched the Carlsberg Meridian 14 and the 2MASS Point Source catalogs to select candidate nearby bright M dwarfs distributed over ~ 25,000 deg^2. Here, we present reconnaissance low-resolution optical spectra ... More
X-ray variability of sigma Orionis young stars with ROSATMar 27 2009We used the Aladin Virtual Obsrvatory tool and High Resolution Imager ROSAT archival data to search for X-ray variability in scale of days in 23 young stars in the sigma Orionis cluster and a background galaxy. Five stars displayed unambiguous flares ... More
Macroscopic quantum self-trapping in a Bose-Josephson junction with fermionsMar 28 2008We study the macroscopic quantum self-trapping effect in a mixture of Bose-Einstein condensate and a large number of quantum degenerate fermions, trapped in a double-well potential with a variable separation between the wells. The large number of fermions ... More
Assessing Learning Outcomes in Middle-Division Classical Mechanics: The Colorado Classical Mechanics/Math Methods InstrumentJun 10 2016Reliable and validated assessments of introductory physics have been instrumental in driving curricular and pedagogical reforms that lead to improved student learning. As part of an effort to systematically improve our sophomore-level Classical Mechanics ... More
Weak Quasielastic Production of Hyperons and Threshold Production of Two PionsFeb 08 2015We have studied quasielastic charged current hyperon production induced by $\bar\nu_\mu$ on free nucleon and the nucleons bound inside the nucleus and the results are presented for several nuclear targets like $^{40}Ar$, $^{56}Fe$ and $^{208}Pb$. The ... More
Superscaling and Neutral Current Quasielastic Neutrino-Nucleus Scattering beyond the Relativistic Fermi Gas ModelJun 01 2007The superscaling analysis is extended to include quasielastic (QE) scattering via the weak neutral current of neutrinos and antineutrinos from nuclei. The scaling function obtained within the coherent density fluctuation model (used previously in calculations ... More
Off-shell effects in the relativistic mean field model and their role in CC (anti)neutrino scattering at MiniBooNE kinematicsOct 02 2013The relativistic mean field (RMF) model is used to describe nucleons in the nucleus and thereby to evaluate the effects of having dynamically off-shell spinors. Compared with free, on-shell nucleons as employed in some other models, within the RMF nucleons ... More
Relativistic description of final-state interactions in neutral-current neutrino and antineutrino cross sectionsJul 16 2013We evaluate semi-inclusive neutral-current quasielastic differential neutrino and antineutrino cross sections within the framework of the relativistic impulse approximation. The results of the relativistic mean field and of the relativistic Green's function ... More
Superscaling in electron-nucleus scattering and its link to CC and NC QE neutrino-nucleus scatteringMar 26 2013The superscaling approach (SuSA) to neutrino-nucleus scattering, based on the assumed universality of the scaling function for electromagnetic and weak interactions, is reviewed. The predictions of the SuSA model for bot CC and NC differential and total ... More
The INTEGRAL-OMC Scientific ArchiveOct 21 2008The Optical Monitoring Camera (OMC) on-board the INTEGRAL satellite has, as one of its scientific goals, the observation of a large number of variable sources previously selected. After almost 6 years of operations, OMC has monitored more than 100 000 ... More
On the Prevalence and Nature of Computational Instruction in Undergraduate Physics Programs across the United StatesDec 20 2017A national survey of physics faculty was conducted to investigate the prevalence and nature of computational instruction in physics courses across the United States. 1246 faculty from 357 unique institutions responded to the survey. The initial results ... More
On a $q$-analogue of the number of representations of an integer as a sum of two squaresJan 09 2018Kassel and Reutenauer \cite{kassel2016fourier} introduced a $q$-analogue of the number of representations of an integer as a sum of two squares. We establish some connections between the prime factorization of $n$ and the coefficients of this $q$-analogue. ... More
A relationship between the ideals of $\mathbb{F}_q\left[x, y, x^{-1}, y^{-1} \right]$ and the Fibonacci numbersSep 13 2017Let $C_n(q)$ be the number of ideals of codimension $n$ of $\mathbb{F}_q\left[x, y, x^{-1}, y^{-1} \right]$, where $\mathbb{F}_q$ is the finite field with $q$ elements. Kassel and Reutenauer [KasselReutenauer2015A] proved that $C_n(q)$ is a polynomial ... More
Relative positions of points on the real line and balanced parenthesesSep 13 2017Consider a finite set of positive real numbers $S$. For any real number $\lambda > 1$, a Dyck word denoted $\langle\! \langle S \rangle\! \rangle_{\lambda} \in \{a,b\}^{\ast}$, was defined in [CaballeroWords2017] in order to compute Hooley's $\Delta$-function ... More
Parity violation in quasielastic electron scattering from closed-shell nucleiOct 03 1995The electromagnetic and weak neutral current matrix elements that enter in the analysis of parity-violating quasielastic electron scattering are calculated using a continuum nuclear shell model. New approximations to the on-shell relativistic one-body ... More
On a function introduced by Erdös and NicolasSep 27 2017Erd\"os and Nicolas [erdos1976methodes] introduced an arithmetical function $F(n)$ related to divisors of $n$ in short intervals $\left] \frac{t}{2}, t\right]$. The aim of this note is to prove that $F(n)$ is the largest coefficient of polynomial $P_n(q)$ ... More
Divisors on overlapped intervals and multiplicative functionsSep 27 2017Consider the real numbers $$ \ell_{n,k} = \ln\left( \tfrac{3}{2}\,k+\sqrt{\left(\tfrac{3}{2}\,k \right)^2 + 3\,n} \right) $$ and the intervals $\mathcal{L}_{n,k} = \left]\ell_{n,k}-\ln 3,\ell_{n,k}\right]$. For all $n \geq 1$, define $$ \frac{L_n(q)}{q^{n-1}} ... More
Relativistic model of 2p-2h meson exchange currents in (anti)neutrino scatteringApr 28 2016We develop a model of relativistic, charged meson-exchange currents (MEC) for neutrino-nucleus interactions. The two-body current is the sum of seagull, pion-in-flight, pion-pole and $\Delta$-pole operators. These operators are obtained from the weak ... More
Angular distribution in two-particle emission induced by neutrinos and electronsJul 26 2014Oct 15 2014The angular distribution of the phase space arising in two-particle emission reactions induced by electrons and neutrinos is computed in the laboratory (Lab) system by boosting the isotropic distribution in the center of mass (CM) system used in Monte ... More
Middle divisors and $σ$-palindromic Dyck wordsSep 13 2017Sep 23 2017Given a real number $\lambda > 1$, we say that $d|n$ is a $\lambda$-middle divisor of $n$ if $$ \sqrt{\frac{n}{\lambda}} < d \leq \sqrt{\lambda n}. $$ We will prove that there are integers having an arbitrarily large number of $\lambda$-middle divisors. ... More
Factorization of Dyck words and the distribution of the divisors of an integerSep 13 2017In [CaballeroHooleyDelta], we associated a Dyck word $\langle\! \langle n \rangle\! \rangle_{\lambda}$ to any pair $(n, \lambda)$ consisting of an integer $n \geq 1$ and a real number $\lambda > 1$. The goal of the present paper is to show a relationship ... More
On prime numbers of the form $2^n \pm k$Sep 13 2017Consider the set $\mathcal{K}$ of integers $k$ for which there are infinitely many primes $p$ such that $p+k$ is a power of $2$. The aim of this paper is to show a relationship between $\mathcal{K}$ and the limits points of some set rational numbers related ... More
Elementary number-theoretical statements proved by Language TheorySep 27 2017We introduce a method to derive theorems from Elementary Number Theory by means of relationships among formal languages. Using $\sigma$-algebras, we define what a proof of a number-theoretical statement by Language Theory means. We prove that such a proof ... More
Stable nematic droplets with handlesDec 08 2012Apr 25 2013We stabilize nematic droplets with handles against surface-tension-driven instabilities using a yield-stress material as outer fluid and study the complex nematic textures and defect structures that result from the competition between topological constraints ... More
Comparing the Matter and Interactions Curriculum with a Traditional Physics Curriculum: A Think Aloud StudyNov 24 2010Physics curricula across the US fail to prepare students adequately to solve problems, especially novel problems. A new curriculum, Matter and Interactions (M&I), was designed to improve student learning by organizing concepts around fundamental principles. ... More
Local Luminous Infrared Galaxies. III. Co-evolution of Black Hole Growth and Star Formation Activity?Jan 17 2013Local luminous infrared (IR) galaxies (LIRGs) have both high star formation rates (SFR) and a high AGN (Seyfert and AGN/starburst composite) incidence. Therefore, they are ideal candidates to explore the co-evolution of black hole (BH) growth and star ... More
Superscaling analysis of inclusive electron scattering and its extension to charge-changing neutrino-nucleus cross sections beyond the relativistic Fermi gas approachSep 19 2006Superscaling analyses of inclusive electron scattering from nuclei are extended from the quasielastic processes to the delta excitation region. The calculations of $(e,e^\prime)$ cross sections for the target nucleus $^{12}$C at various incident electron ... More
The LHCb pentaquark as a $\bar{D}^*Σ_c-\bar{D}^*Σ_c^*$ molecular stateJul 15 2015Oct 21 2015We perform a theoretical analysis of the $\Lambda_b \to J/\psi K^- p$ reaction from where a recent LHCb experiment extracts a $\Lambda(1405)$ contribution in the $K^- p$ spectrum close to threshold and two baryon states of hidden charm in the $J/\psi\,p$ ... More
Regge signatures from forward CLAS $Λ(1520)$ photoproduction dataMay 13 2014The $\gamma p \to K^+ \Lambda(1520)$ reaction mechanism is investigated within a Regge--effective Lagrangian hybrid approach based on our previous study of this reaction [Physical Review C89, 015203 (2014)]. Near threshold and for large $K^+$ angles, ... More
Scaling Function, Spectral Function and Nucleon Momentum Distribution in NucleiApr 01 2011The link between the scaling function extracted from the analysis of (e,e') cross sections and the spectral function/momentum distribution in nuclei is revisited. Several descriptions of the spectral function based on the independent particle model are ... More
Music and AstronomyOct 11 2008Oct 16 2008What do Brian May (the Queen's lead guitarist), William Herschel and the Jupiter Symphony have in common? And a white dwarf, a piano and Lagartija Nick? At first glance, there is no connection between them, nor between Music and Astronomy. However, there ... More
On the asymptotic behaviour of increasing positive self-similar Markov processesNov 12 2007We are interested by the rate of growth of increasing positive self-similar Markov processes (ipssMp) such that the subordinator associated to it via Lamperti's transformation has infinite mean. We prove that the logarithm of an ipssMp normalized by the ... More
Geometric properties of surfaces with the same mean curvature in R^3 and L^3Apr 14 2016Spacelike surfaces in the Lorentz-Minkowski space L^3 can be endowed with two different Riemannian metrics, the metric inherited from L^3 and the one induced by the Euclidean metric of R^3. It is well known that the only surfaces with zero mean curvature ... More
Activity from the Be/X-ray binary system V0332+53 during its intermediate-luminosity outburst in 2008Jun 29 2015Jan 13 2016Aims: We present a study of the Be/X-ray binary system V 0332+53 with the main goal of characterizing its behavior mainly during the intermediate-luminosity X-ray event on 2008. In addition, we aim to contribute to the understanding of the global behavior ... More
Planck Spectroscopy and the Quantum Noise of Microwave Beam SplittersMar 16 2010We use a correlation function analysis of the field quadratures to characterize both the black body radiation emitted by a 50 Ohm load resistor and the quantum properties of two types of beam splitters in the microwave regime. To this end, we first study ... More
Photon emission in neutral current interactions at intermediate energiesNov 09 2013Neutral current photon emission reactions with nucleons and nuclei are studied. These processes are important backgrounds for nu_mu to nu_e (bar(nu)_mu to bar(nu)_e) appearance oscillation experiments where electromagnetic showers instigated by electrons ... More
Re-analysis of the $Λ(1520)$ photoproduction reactionSep 27 2013Feb 19 2014Based on previous studies that support the important role of the $N^*(2120) D_{13}$ resonance in the $\gamma p \to K^+ \Lambda(1520)$ reaction, we make a re-analysis of this $\Lambda(1520)$ photoproduction reaction taking into account the recent CLAS ... More
Dual-path state reconstruction scheme for propagating quantum microwaves and detector noise tomographyJan 20 2010Mar 11 2010Quantum state reconstruction involves measurement devices that are usually described by idealized models, but not known in full detail in experiments. For weak propagating microwaves, the detection process requires linear amplifiers which obscure the ... More
Albus 1: A very bright white dwarf candidateJul 09 2007We have serendipitously discovered a previously-unknown, bright source (B_T = 11.75+/-0.07 mag) with a very blue V_T-K_s color, to which we have named Albus 1. A photometric and astrometric study using Virtual Observatory tools has shown that it possesses ... More
Young stars and brown dwarfs surrounding Alnilam (eps Ori) and Mintaka (del Ori)Apr 14 2008Aims: We look for new regions for the search of substellar objects. Methods: Two circular areas, 45 arcmin-radius each, centred on the young massive star systems Alnilam and Mintaka in the Orion Belt, have been explored. The regions are very young (less ... More
Recent activity of the Be/X-ray binary system SAX J2103.5+4545May 16 2014Aims. We present a multiwavelength study of the Be/X-ray binary system SAX J2103.5+4545 with the goal of better characterizing the transient behaviour of this source. Methods. SAX J2103.5+4545 was observed by Swift-XRT four times in 2007 from April 25 ... More
Bloch oscillations of ultracold atoms: a tool for a metrological determination of $h/m_{Rb}$May 03 2004We use Bloch oscillations in a horizontal moving standing wave to transfer a large number of photon recoils to atoms with a high efficiency (99.5% per cycle). By measuring the photon recoil of $^{87}Rb$, using velocity selective Raman transitions to select ... More
Emission of neutron-proton and proton-proton pairs in electron scattering induced by meson-exchange currentsJun 21 2016We use a relativistic model of meson-exchange currents to compute the proton-neutron and proton-proton yields in $(e,e')$ scattering from $^{12}$C in the 2p-2h channel. We compute the response functions and cross section with the relativistic Fermi gas ... More
Emission of neutron-proton and proton-proton pairs in neutrino scatteringJul 28 2016We use a recently developed model of relativistic meson-exchange currents to compute the neutron-proton and proton-proton yields in $(\nu_\mu,\mu^-)$ scattering from $^{12}$C in the 2p-2h channel. We compute the response functions and cross sections with ... More
Cygnus X-3 transition from the ultrasoft to the hard stateAug 03 2007Aug 06 2007Aims: The nature of Cygnus X-3 is still not understood well. This binary system might host a black hole or a neutron star. Recent observations by INTEGRAL have shown that Cygnus X-3 was again in an extremely ultrasoft state. Here we present our analysis ... More
Estimate of the theoretical uncertainty of the cross sections for nucleon knockout in neutral-current neutrino-oxygen interactionsJun 08 2015Free nucleons propagating in water are known to produce gamma rays, which form a background to the searches for diffuse supernova neutrinos and sterile neutrinos carried out with Cherenkov detectors. As a consequence, the process of nucleon knockout induced ... More
Meson-Baryon s-wave Resonances with Strangeness -3Oct 26 2006Starting from a consistent SU(6) extension of the Weinberg-Tomozawa (WT) meson-baryon chiral Lagrangian (Phys. Rev. D74 (2006) 034025), we study the s-wave meson-baryon resonances in the strangeness S=-3 and negative parity sector. Those resonances are ... More
The role of $N^*(2120)$ nucleon resonance in $KΛ(1520)$ photon and hadronic productionsNov 03 2013The associate $K\Lambda(1520)$ photon and hadronic production in the $\gamma p \to K^+\Lambda(1520)$, $p p \to p K^+ \Lambda(1520)$ and $\pi^- p \to K^0 \Lambda(1520)$ reactions are investigated within the effective Lagrangian approach and the isobar ... More
Bivalent defect configurations in inhomogeneous nematic shellsNov 19 2012We present a theoretical study of the director fields and energetics of nematic liquid crystal shells with two pairs of surface defects. The pairs of defects can undergo abrupt transitions between a configuration of maximum separation to at state in which ... More
X-Ray and Optical Observations of A 0535+26Sep 19 2011Oct 16 2012We present recent contemporaneous X-ray and optical observations of the Be/X-ray binary system A\,0535+26 with the \textit{Fermi}/Gamma-ray Burst Monitor (GBM) and several ground-based observatories. These new observations are put into the context of ... More
Scaling limits of general population processes - Wright-Fisher and branching processes in random environmentFeb 07 2018Our motivation comes from the large population approximation of individual based models in population dynamics and population genetics. We propose a general method to investigate scaling limits of finite dimensional population size Markov chains to diffusion ... More
Quantum optical lattices for emergent many-body phases of ultracold atomsApr 24 2015Nov 10 2015Confining ultracold gases in cavities creates a paradigm of quantum trapping potentials. We show that this allows to bridge models with global collective and short-range interactions as novel quantum phases possess properties of both. Some phases appear ... More
Rotational Surfaces in $\mathbb{L}^3$ and Solutions in the Nonlinear Sigma ModelMay 15 2007Nov 13 2008The Gauss map of non-degenerate surfaces in the three-dimensional Minkowski space are viewed as dynamical fields of the two-dimensional O(2,1) Nonlinear Sigma Model. In this setting, the moduli space of solutions with rotational symmetry is completely ... More
Ranked Document Retrieval in (Almost) No SpaceJul 23 2012Ranked document retrieval is a fundamental task in search engines. Such queries are solved with inverted indexes that require additional 45%-80% of the compressed text space, and take tens to hundreds of microseconds per query. In this paper we show how ... More
Self-Similar Algebras with connections to Run-length Encoding and Rational LanguagesSep 13 2017A self-similar algebra $\left(\mathfrak{A}, \psi \right)$ is an associative algebra $\mathfrak{A}$ with a morphism of algebras $\psi: \mathfrak{A} \longrightarrow M_d \left( \mathfrak{A}\right)$, where $M_d \left( \mathfrak{A}\right)$ is the set of $d\times ... More
Testing nuclear models via neutrino scatteringNov 21 2014Recent progresses on the relativistic modeling of neutrino-nucleus reactions are presented and the results are compared with high precision experimental data in a wide energy range.
Remarks on the $P_c$ structures and triangle singularitiesMay 17 2016Sep 19 2016It was proposed that the narrow $P_c(4450)$ structure observed by the LHCb Collaboration in the reaction $\Lambda_b\to J/\psi p K$ might be due to a triangle singularity around the $\chi_{c1}$--proton threshold at 4.45~GeV. We discuss the occurrence of ... More
Pathways to quiescence: SHARDS view on the Star Formation Histories of massive quiescent galaxies at 1.0 < z < 1.5Jul 28 2015Jan 21 2016We present Star Formation Histories (SFHs) for a sample of 104 massive (stellar mass M > 10$^{10}$ M$_{\odot}$) quiescent galaxies (MQGs) at $z$=1.0-1.5 from the analysis of spectro-photometric data from the SHARDS and HST/WFC3 G102 and G141 surveys of ... More
CARMENES input catalogue of M dwarfs II. High-resolution imaging with FastCamAug 29 2016Aims: We search for low-mass companions of M dwarfs and characterize their multiplicity fraction with the purpose of helping in the selection of the most appropriate targets for the CARMENES exoplanet survey. Methods: We obtained high-resolution images ... More
X-ray absorption, nuclear infrared emission and dust covering factors of AGN: testing Unification SchemesJan 18 2016Jan 22 2016We present the distributions of geometrical covering factors of active galactic nuclei (AGNs) dusty tori (f2) using an X-ray selected complete sample of 227 AGN drawn from the Bright Ultra-hard XMM-Newton Survey. The AGN have z from 0.05 to 1.7, 2-10 ... More
SHARDS: Constraints on the dust attenuation law of star-forming galaxies at z~2Jan 03 2018We make use of SHARDS, an ultra-deep (<26.5AB) galaxy survey that provides optical photo-spectra at resolution R~50, via medium band filters (FWHM~150A). This dataset is combined with ancillary optical and NIR fluxes to constrain the dust attenuation ... More
Neutrino Interactions Importance for Nuclear PhysicsSep 07 2009We review the general interplay between Nuclear Physics and neutrino-nucleus cross sections at intermediate and high energies. The effects of different reaction mechanisms over the neutrino observables are illustrated with examples in calculations using ... More
Joint H-alpha and X-Ray Observations of Massive X-Ray Binaries. II. The Be X-ray Binary and Microquasar LS I +61 303Oct 19 2006We present the results of an H-alpha monitoring campaign on the BeXRB and microquasar system LS I +61 303. We use radial velocity measurements of HeI lines in our spectra to re-evaluate the orbital elements and to better establish the time of periastron. ... More
CARMENES input catalogue of M dwarfs. I. Low-resolution spectroscopy with CAFOSFeb 26 2015Context. CARMENES is a stabilised, high-resolution, double-channel spectrograph at the 3.5 m Calar Alto telescope. It is optimally designed for radial-velocity surveys of M dwarfs with potentially habitable Earth-mass planets. Aims. We prepare a list ... More
A Lattice Study of Semi-leptonic Decays of $D$-MesonsDec 02 1994We present results of a lattice computation of the matrix elements of the vector and axial-vector currents which are relevant for the semi-leptonic decays $D \rightarrow K$ and $D \rightarrow K^*$. The computations are performed in the quenched approximation ... More
Liquid-gas separation in colloidal electrolytesAug 10 2005Oct 26 2005The liquid-gas transition of an electroneutral mixture of oppositely charged colloids, studied by Monte Carlo simulations, is found in the low temperature -- low density region. The critical temperature shows a non-monotonous behavior as a function of ... More
A complete census of silicate features in the mid-infrared spectra of active galaxiesFeb 20 2015We present a comprehensive study of the silicate features at 9.7 and 18 micron of a sample of almost 800 active galactic nuclei (AGN) with available spectra from the Spitzer InfraRed Spectrograph (IRS). We measure the strength of the silicate feature ... More
Development of a modes of collaboration frameworkNov 04 2016Group work is becoming increasingly common in introductory physics classrooms. Understanding how students engage in these group learning environments is important for designing and facilitating productive learning opportunities for students. We conducted ... More
Proof(s) of the Lamperti representation of Continuous-State Branching ProcessesFeb 19 2008Sep 15 2009This paper uses two new ingredients, namely stochastic differential equations satisfied by continuous-state branching processes (CSBPs), and a topology under which the Lamperti transformation is continuous, in order to provide self-contained proofs of ... More
The Plastic and Liquid Phases of CCl$_3$Br Studied by Molecular Dynamics SimulationsJul 12 2013We present a molecular dynamics study of the liquid and plastic crystalline phases of CCl$_3$Br. We investigated the short-range orientational order using a recently developed classification method and we found that both phases behave in a very similar ... More
The CARMENES search for exoplanets around M dwarfs: Wing asymmetries of H$α$, Na I D, and He I linesJan 31 2018Stellar activity is ubiquitously encountered in M dwarfs and often characterised by the H$\alpha$ line. In the most active M dwarfs, H$\alpha$ is found in emission, sometimes with a complex line profile. Previous studies have reported extended wings and ... More
Compressed String DictionariesJan 28 2011The problem of storing a set of strings --- a string dictionary --- in compact form appears naturally in many cases. While classically it has represented a small part of the whole data to be processed (e.g., for Natural Language processing or for indexing ... More
Compressed Vertical Partitioning for Full-In-Memory RDF ManagementOct 18 2013Oct 21 2013The Web of Data has been gaining momentum and this leads to increasingly publish more semi-structured datasets following the RDF model, based on atomic triple units of subject, predicate, and object. Although it is a simple model, compression methods ... More
Charming BaryonsOct 01 2013We study odd-parity baryonic resonances with one heavy and three light flavors, dynamically generated by meson-baryon interactions. Special attention is paid to Heavy Quark Spin Symmetry (HQSS), hence pseudoscalar and vector mesons and baryons with J^P ... More
Charmed and strange baryon resonances with heavy-quark spin symmetryFeb 10 2012Jul 04 2012We study charmed and strange baryon resonances that are generated dynamically by a unitary baryon-meson coupled-channel model which incorporates heavy-quark spin symmetry. This is accomplished by extending the SU(3) Weinberg-Tomozawa chiral Lagrangian ... More