Results for "F. D. Amaro"

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High-gain DC-mode operated Gaseous Photomultipliers for the visible spectral rangeAug 11 2008Aug 12 2008We shortly describe recent progress in photon detectors combining bi-alkali photocathodes and cascaded patterned gas-avalanche electron multipliers. It permitted the development and the first feasibility demonstration of high-gain gaseous photomultipliers ... More
The Photon-Assisted Cascaded Electron Multiplier: a Concept for Potential Avalanche-Ion BlockingJun 25 2006We present a Photon-Assisted Cascaded Electron Multipliers (PACEM) which has a potential for ion back-flow blocking in gaseous radiation detectors: the avalanche from a first multiplication stage propagates to the successive one via its photons, which ... More
The Thick-COBRA: a New Gaseous Electron Multiplier for Radiation DetectorsAug 04 2010The operation principle and preliminary results of a novel gas-avalanche patterned hole electron multiplier, the Thick-COBRA (THCOBRA), are presented. This micro-hole structure is derived from the THGEM and MHSP. Sub-millimeter diameter holes are mechanically ... More
Development of high-gain gaseous photomultipliers for the visible spectral rangeMay 01 2009May 05 2009We summarize the development of visible-sensitive gaseous photomultipliers, combining a semitransparent bi-alkali photocathode with a state-of-the-art cascaded electron multiplier. The latter has high photoelectron collection efficiency and a record ion ... More
Further progress in ion back-flow reduction with patterned gaseous hole-multipliersJun 25 2007Aug 14 2007A new idea on electrostatic deviation and capture of back-drifting avalanche-ions in cascaded gaseous hole-multipliers is presented. It involves a flipped reversed-bias Micro-Hole & Strip Plate (F-R-MHSP) element, the strips of which are facing the drift ... More
Advances in ion back-flow reduction in cascaded gaseous electron multipliers incorporating R-MHSP elementsJul 03 2006A new concept is presented for the reduction of ion back-flow in GEM-based cascaded gaseous electron multipliers, by incorporating Micro-Hole & Strip Plate (MHSP) elements operating in reversed-bias mode (R-MHSP). About an order of magnitude reduction ... More
Operation of MHSP multipliers in high pressure pure noble-gasJan 17 2006We report on the performance of a Micro-Hole & Strip Plate (MHSP) electron multiplier operating in pure Xe, Kr, Ar and Ne at the pressure range of 1 to 6 bar. The maximal gains at 1 bar Xe and Kr are 50000 and 100000, respectively; they drop by about ... More
High pressure operation of the Photon-Assisted Cascaded Electron MultiplierJul 31 2008We present the operation of the recently introduced Photon Assisted Cascaded Electron Multiplier (PACEM) in xenon at high pressure. The PACEM is a multi step electron multiplier where the VUV scintillation produced in the electron avalanches is used for ... More
Efficient ion blocking in gaseous detectors and its application to gas-avalanche photomultipliers sensitive in the visible-light rangeApr 28 2008A novel concept for ion blocking in gas-avalanche detectors was developed, comprising cascaded micro-hole electron multipliers with patterned electrodes for ion defocusing. This leads to ion blocking at the 10^{-4} level, in DC mode, in operation conditions ... More
Gain characteristics of a 100 micrometer thick GEM in Krypton-CO2 mixturesJan 11 2018The operation of a Micropattern Gaseous Detector (MPGD) comprising a cascade of two non-standard Gas Electron Multipliers (GEM) made from a 100 micrometer kapton foil was evaluated in pure krypton and in krypton-CO2 mixtures. The final avalanche charge ... More
Ion-induced effects in GEM & GEM/MHSP gaseous photomultipliers for the UV and the visible spectral rangeFeb 24 2005We report on the progress in the study of cascaded GEM and GEM/MHSP gas avalanche photomultipliers operating at atmospheric pressure, with CsI and bialkali photocathodes. They have single-photon sensitivity, ns time resolution and good localization properties. ... More
Characterization of the Hamamatsu S8664 Avalanche Photodiode for X-Ray and VUV-light detectionAug 25 2011Jan 05 2012We present the first operation of the Avalanche Photodiode (APD) from Hamamatsu to xenon scintillation light and to direct X-rays of 22.1 keV and 5.9 keV. A large non-linear response was observed for the direct X-ray detection. At 415 V APD bias voltage ... More
The role of the supermassive black hole spin in the estimation of the EMRI event rateMay 21 2012Dec 06 2012A common result to all EMRI investigations on rates is that the possibility that a compact object merges with the MBH after only one intense burst of GWs is much more likely than a slow adiabatic inspiral, an EMRI. The later is referred to as a "plunge" ... More
Tidal disruptions of separated binaries in galactic nucleiJun 07 2011Apr 25 2012Several galaxies have exhibited X-ray flares that are consistent with the tidal disruption of a star by a central supermassive black hole. In theoretical treatments of this process it is usually assumed that the star was initially on a nearly parabolic ... More
The Resistive-Plate WELL with Argon mixtures - a robust gaseous radiation detectorMar 15 2016A thin single-element THGEM-based, Resistive-Plate WELL (RPWELL) detector was operated with 150 GeV/c muon and pion beams in Ne/(5%CH$_4$), Ar/(5%CH$_4$) and Ar/(7%CO$_2$); signals were recorded with 1 cm$^2$ square pads and SRS/APV25 electronics. Detection ... More
In-beam evaluation of a medium-size Resistive-Plate WELL gaseous particle detectorJul 09 2016Sep 08 2016In-beam evaluation of a fully-equipped medium-size 30$\times$30 cm$^2$ Resistive Plate WELL (RPWELL) detector is presented. It consists here of a single element gas-avalanche multiplier with Semitron ESD225 resistive plate, 1 cm$^2$ readout pads and APV25/SRS ... More
Investigating the retention of intermediate-mass black holes in star clusters using N-body simulationsAug 25 2011May 27 2013Contrary to supermassive and stellar-mass black holes (SBHs), the existence of intermediate-mass black holes (IMBHs) with masses ranging between 10^{2-5} Msun has not yet been confirmed. The main problem in the detection is that the innermost stellar ... More
Effects of Short-Range Correlations in (e,e'p) reactions and nuclear overlap functionsJul 06 2001A study of the effects of short-range correlations over the (e,e'p) reaction for low missing energy in closed shell nuclei is presented. We use correlated, quasi-hole overlap functions extracted from the asymptotic behavior of the one-body density matrix, ... More
First in-beam studies of a Resistive-Plate WELL gaseous multiplierOct 12 2015Jan 20 2016We present the results of the first in-beam studies of a medium size (10$\times$10 cm$^2$) Resistive-Plate WELL (RPWELL): a single-sided THGEM coupled to a pad anode through a resistive layer of high bulk resistivity ($\sim$10$^9 \Omega$cm). The 6.2~mm ... More
Gravitational Waves Notes, Issue #4 : "A Roadmap to Fundamental Physics from LISA EMRI Observations"Sep 07 2010GW Notes was born from the need for a journal where the distinct communities involved in gravitation wave research might gather. While these three communities - Astrophysics, General Relativity and Data Analysis - have made significant collaborative progress ... More
Blocking low-eccentricity EMRIs: A statistical direct-summation N-body study of the Schwarzschild barrierNov 23 2012The capture of a compact object in a galactic nucleus by a massive black hole (MBH), an extreme-mass ratio inspiral (EMRI), is the best way to map space and time around it. Recent work on stellar dynamics has demonstrated that there seems to be a complot ... More
Meson Exchange Currents in (e,e'p) recoil polarization observablesMay 26 2003Jul 31 2003A study of the effects of meson-exchange currents and isobar configurations in $A(\vec{e},e'\vec{p})B$ reactions is presented. We use a distorted wave impulse approximation (DWIA) model where final-state interactions are treated through a phenomenological ... More
Induced Nucleon Polarization and Meson-Exchange Currents in (e,e'p) ReactionsFeb 02 2004May 11 2004Nucleon recoil polarization observables in $(e,e'\vec{p})$ reactions are investigated using a semi-relativistic distorted-wave model which includes one- and two-body currents with relativistic corrections. Results for the induced polarization asymmetry ... More
Pionic DeuteriumFeb 23 2010The strong interaction shift and broadening in pionic deuterium have been remeasured with high statistics by means of the (3p-1s) X-ray transition using the cyclotron trap and a high-resolution crystal spectrometer. Preliminary results are (-2325+/-31) ... More
Precision determination of the dpi -> NN transition strength at thresholdMar 22 2010An unusual but effective way to determine at threshold the dpi -> NN transition strength is to exploit the hadronic ground-state broadening in pionic deuterium, accessible by x-ray spectroscopy. The broadening is dominated by the true absorption channel ... More
Infalling clouds onto super-massive black hole binaries - I. Formation of discs, accretion and gas dynamicsJul 20 2015Oct 22 2015There is compelling evidence that most -if not all- galaxies harbour a super-massive black hole (SMBH) at their nucleus, hence binaries of these massive objects are an inevitable product of the hierarchical evolution of structures in the universe, and ... More
Experiments towards resolving the proton charge radius puzzleSep 10 2015Oct 17 2015We review the status of the proton charge radius puzzle. Emphasis is given to the various experiments initiated to resolve the conflict between the muonic hydrogen results and the results from scattering and regular hydrogen spectroscopy.
Characterization of large area avalanche photodiodes in X-ray and VUV-light detectionFeb 15 2007The present manuscript summarizes novel studies on the application of large area avalanche photodiodes (LAAPDs) to the detection of X-rays and vacuum ultraviolet (VUV) light. The operational characteristics of four different LAAPDs manufactured by Advanced ... More
Meson-exchange currents and quasielastic predictions for charged-current neutrino-12C scattering in the superscaling approachDec 04 2014Apr 14 2015We evaluate and discuss the impact of meson-exchange currents (MECs) on charged-current quasielastic neutrino cross sections. We consider the nuclear transverse response arising from two-particle two-hole states excited by the action of electromagnetic, ... More
Final-state interaction and recoil polarization in (e,e'p) reactions: comparison with the polarized target caseNov 22 2004A study of the total cross section for polarized proton knockout in $(e,e'{\vec p})$ reactions is carried out for the closed-shell nucleus $^{40}$Ca. The dependence of FSI effects on polarization observables viewed as functions of the nucleon polarization ... More
Relativistic total cross section and angular distribution for Rayleigh scattering by atomic hydrogenMar 07 2012Mar 27 2012We study the total cross section and angular distribution in Rayleigh scattering by hydrogen atom in the ground state, within the framework of Dirac relativistic equation and second-order perturbation theory. The relativistic states used for the calculations ... More
Research Update on Extreme-Mass-Ratio InspiralsOct 03 2014The inspirals of stellar-mass mass compact objects into massive black holes in the centres of galaxies are one of the most important sources of gravitational radiation for space-based detectors like LISA or eLISA. These extreme-mass-ratio inspirals (EMRIs) ... More
Meson-exchange currents and quasielastic neutrino cross sections in the SuperScaling Approximation modelOct 08 2010Nov 30 2010We evaluate the quasielastic double differential neutrino cross sections obtained in a phenomenological model based on the superscaling behavior of electron scattering data. We compare our results with the recent experimental data for neutrinos of MiniBooNE ... More
Pionic deuteriumNov 10 2010Jul 12 2011The strong interaction shift $\epsilon$ and broadening {\Gamma} in pionic deuterium have been determined in a high statistics study of the {\pi}D(3p - 1s) X-ray transition using a high-resolution crystal spectrometer. The pionic deuterium shift will provide ... More
Surface Brightness Profile of the Milky Way's Nuclear Star ClusterMar 26 2014Jun 17 2014(abridged) In this paper we aim at determining the shape, size, and luminosity/mass of the Milky Way Nuclear Star Cluster (MWNSC). We use Spitzer/IRAC images at 3.6 and 4.5 micrometer, where interstellar extinction is at a minimum but the overall emission ... More
Inclusive electron scattering within the SuSAv2-MEC approachMar 28 2016Jul 28 2016We present our recent progress on the relativistic modeling of electron-nucleus reactions and compare our predictions with inclusive $^{12}$C ($e,e'$) experimental data in a wide kinematical region. The model, originally based on the superscaling phenomenon ... More
The next generation of laser spectroscopy experiments using light muonic atomsAug 22 2018Precision spectroscopy of light muonic atoms provides unique information about the atomic and nuclear structure of these systems and thus represents a way to access fundamental interactions, properties and constants. One application comprises the determination ... More
Electron scattering with a short-range correlation modelOct 08 1999The inclusive electromagnetic responses in the quasi-elastic region are calculated with a model which considers the terms of the cluster expansion containinga single correlation line. The validity of this model is studied by comparing, in nuclear matter, ... More
Semi-relativistic meson exchange currents in (e,e') and (e,e'p) reactionsFeb 03 2003May 20 2003Electron-induced one-nucleon knock-out observables are computed for moderate to high momentum transfer making use of semi-relativistic expressions for the one-body and two-body meson-exchange current matrix elements. Emphasis is placed on the semi-relativistic ... More
Quantized form factor shift in the presence of free electron laser radiationJul 25 2015In electron scattering, the target form factors contribute significantly to the diffraction pattern and carry information on the target electromagnetic charge distribution. Here we show that the presence of electromagnetic radiation, as intense as currently ... More
Parametrization of the angular correlation and degree of linear polarization in two-photon decays of hydrogen-like ionsAug 15 2012The two-photon decay in hydrogen-like ions is investigated within the framework of second order perturbation theory and Dirac's relativistic equation. Special attention is paid to the angular correlation of the emitted photons as well as to the degree ... More
Calculation of the two-photon decay rates of hydrogen-like ions by using B-polynomialsApr 25 2011A new approach is laid out to investigate the two photon atomic transitions. It is based on application of the finite basis solutions constructed from the Bernstein Polynomial (B-Polynomial) sets. We show that such an approach provides a very promising ... More
Resonant effects on the two-photon emission from hydrogenic ionsApr 04 2009A theoretical study the all two-photon transitions from initial bound states with ni = 2, 3 in hydrogenic ions is presented. High-precision values of relativistic decay rates for ions with nuclear charge in the range 1 =< Z =< 92 are obtained through ... More
Analytical evaluation of atomic form factors: application to Rayleigh scatteringAug 30 2014Atomic form factors are widely used for the characterization of targets and specimens, from crystallography to biology. By using recent mathematical results, here we derive an analytical expression for the atomic form factor within the independent particle ... More
Planar LAAPDs: Temperature Dependence, Performance, and Application in Low Energy X-ray SpectroscopyOct 15 2004An experiment measuring the 2S Lamb shift in muonic hydrogen mup is being performed at the Paul Scherrer Institute, Switzerland. It requires small and compact detectors for 1.9 keV x rays (2P-1S transition) with an energy resolution around 25% at 2 keV, ... More
Neutrino and antineutrino CCQE scattering in the SuperScaling Approximation from MiniBooNE to NOMAD energiesMay 29 2013Jul 02 2013We compare the predictions of the SuperScaling model for charged current quasielastic muonic neutrino and antineutrino scattering from $^{12}$C with experimental data spanning an energy range up to 100 GeV. We discuss the sensitivity of the results to ... More
Muonic hydrogen cascade time and lifetime of the short-lived $2S$ stateNov 13 2006Metastable ${2S}$ muonic-hydrogen atoms undergo collisional ${2S}$-quenching, with rates which depend strongly on whether the $\mu p$ kinetic energy is above or below the ${2S}\to {2P}$ energy threshold. Above threshold, collisional ${2S} \to {2P}$ excitation ... More
Superscaling of non-quasielastic electron-nucleus scatteringJul 10 2009The present study is focused on the superscaling behavior of electron-nucleus cross sections in the region lying above the quasielastic peak, especially the region dominated by electroexcitation of the Delta. Non-quasielastic cross sections are obtained ... More
Meson-exchange Currents and Quasielastic Neutrino Cross SectionsOct 21 2011We illustrate and discuss the role of meson-exchange currents in quasielastic neutrino-nucleus scattering induced by charged currents, comparing the results with the recent MiniBooNE data for differential and integrated cross sections.
X-MRIs: Extremely Large Mass-Ratio InspiralsMar 26 2019The detection of the gravitational waves (GWs) emitted in the capture process of a compact object by a massive black hole (MBH) is known as an extreme-mass ratio inspiral (EMRI) and represents a unique probe of gravity in the strong regime and is one ... More
Improved X-ray detection and particle identification with avalanche photodiodesMay 26 2015Avalanche photodiodes are commonly used as detectors for low energy x-rays. In this work we report on a fitting technique used to account for different detector responses resulting from photo absorption in the various APD layers. The use of this technique ... More
The distribution of stars around the Milky Way's central black hole II: Diffuse light from sub-giants and dwarfsJan 13 2017Nov 27 2017This is the second of three papers that search for the predicted stellar cusp around the Milky Way's central black hole, Sagittarius A*, with new data and methods. We aim to infer the distribution of the faintest stellar population currently accessible ... More
The distribution of old stars around the Milky Way's central black hole I: Star countsJan 13 2017Nov 27 2017(abridged) In this paper we revisit the problem of inferring the innermost structure of the Milky Way's nuclear star cluster via star counts, to clarify whether it displays a core or a cusp around the central black hole. Through image stacking and improved ... More
Gravitational waves from coalescing massive black holes in young dense clustersOct 16 2006HST observations reveal that young massive star clusters form in gas-rich environments like the Antenn{\ae} galaxy which will merge in collisional processes to form larger structures. These clusters amalgamate and if some of these clusters harbour a massive ... More
Charged-current neutrino-nucleus reactions within the SuSAv2-MEC approachJul 28 2016Jul 29 2016We present a detailed study of charged-current (CC) neutrino-nucleus reactions in a fully relativis- tic framework and comparisons with recent experiments spanning an energy range from hundreds of MeV up to 100 GeV within the SuperScaling Approach, which ... More
The proton radius puzzleJun 02 2017Aug 19 2017High-precision measurements of the proton radius from laser spectroscopy of muonic hydrogen demonstrated up to six standard deviations smaller values than obtained from electron-proton scattering and hydrogen spectroscopy. The status of this discrepancy, ... More
Two-nucleon emission in neutrino and electron scattering from nuclei: the modified convolution approximationJun 20 2017The theoretical formalism of inclusive lepton-nucleus scattering in the two-nucleon emission channel is discussed in the context of a simplified approach, the modified convolution approximation. This allows one to write the 2p2h responses of the relativistic ... More
The frozen nucleon approximation in two-particle two-hole response functionsMar 03 2017We present a fast and efficient method to compute the inclusive two-particle two-hole (2p-2h) electroweak responses in the neutrino and electron quasielastic inclusive cross sections. The method is based on two approximations. The first neglects the motion ... More
MHSP in reversed-biased operation mode for ion blocking in gas-avalanche multipliersMar 31 2005We present recent results on the operation of gas-avalanche detectors comprising a cascade of gas electron multipliers (GEMs) and Micro-Hole and Strip Plates (MHSPs) multiplier operated in reversed-bias (R-MHSP) mode. The operation mechanism of the R-MHSP ... More
Stellar dynamics and extreme-mass ratio inspiralsMay 23 2012Nowadays it is well-established that in the centre of the Milky Way a massive black hole (MBH) with a mass of about four million solar masses is lurking. While there is an emerging consensus about the origin and growth of supermassive black holes (with ... More
Dynamics of dense star-gas systems: BHs and their precursorsFeb 21 2005May 23 2012This thesis embraces several aspects of theoretical stellar dynamics in clusters, both analytically and numerically. We try to elucidate the phenomena currently observed in all types of galaxies, including AGNs and quasars, some of the most powerful objects ... More
Multipartite entanglement dynamics in a cavityOct 13 2014May 27 2015We study the dynamics of two kinds of entanglement, and there interplay. On one hand, the intrinsic entanglement within a central system composed by three two level atoms, and measured by multipartite concurrence, on the other, the entanglement between ... More
The fragmenting past of the disk at the Galactic Center : The culprit for the missing red giantsOct 01 2013Dec 18 2013Since 1996 we have known that the Galactic Center (GC) displays a core-like distribution of red giant branch (RGB) stars starting at ~ 10", which poses a theoretical problem, because the GC should have formed a segregated cusp of old stars. This issue ... More
Sagittarius A* Rivaled the Sun in the Ancient X-ray SkyDec 17 2014Sagittarius A*, lying the Galactic Center $8$ kpc from Earth, hosts the closest supermassive black hole known to us. It is now inactive, but there are evidences indicating that about six million years ago it underwent a powerful outburst where the luminosity ... More
Dense gas-star systems: Super-massive stars evolutionDec 12 2002Feb 28 2003In the 60s and 70s super-massive central objects (from now onwards SMOs) were thought to be the main source of active galactic nuclei (AGNs) characteristics (luminosities of $L \approx 10^{12} L_{\odot}$). The release of gravitational binding energy by ... More
Stability and evolution of super-massive stars (SMS)Sep 17 2003Highly condensed gaseous objects with masses larger than 5x10^4 M_sun are called super-massive stars. In the quasistationary contraction phase, the hydrostatic equilibrium is determined by radiation pressure and gravitation. The global structure is that ... More
Sculpting the Stellar Cusp in the Galactic CenterOct 14 2014Dec 10 2014Observations of the innermost parsec surrounding Sgr A$^*$ ---the supermassive black hole in the center of our Galaxy--- have revealed a diversity of structures whose existence and characteristics apparently defy the fundamental principles of dynamics. ... More
On strong mass segregation around a massive black hole: Implications for lower-frequency gravitational-wave astrophysicsOct 16 2009Oct 18 2009We present, for the first time, a clear $N$-body realization of the {\it strong mass segregation} solution for the stellar distribution around a massive black hole. We compare our $N$-body results with those obtained by solving the orbit-averaged Fokker-Planck ... More
The impact of realistic models of mass segregation on the event rate of extreme-mass ratio inspirals and cusp re-growthOct 27 2010Apr 15 2011One of the most interesting sources of gravitational waves (GWs) for LISA is the inspiral of compact objects on to a massive black hole (MBH), commonly referred to as an "extreme-mass ratio inspiral" (EMRI). The small object, typically a stellar black ... More
Intermediate-mass black holes in colliding clusters: Implications for lower-frequency gravitational-wave astronomyOct 16 2006Observations suggest that star clusters often form in binaries or larger bound groups. Therefore, mergers between two clusters are likely to occur. If these clusters both harbor an intermediate-mass black hole (IMBH; 10^{2-4} Msun) in their center, they ... More
Science with the space-based interferometer LISA. V: Extreme mass-ratio inspiralsMar 28 2017Apr 11 2018The space-based Laser Interferometer Space Antenna (LISA) will be able to observe the gravitational-wave signals from systems comprised of a massive black hole and a stellar-mass compact object. These systems are known as extreme-mass-ratio inspirals ... 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
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
Relativistic mergers of black hole binaries have large, similar masses, low spins and are circularDec 15 2015Feb 29 2016Gravitational waves are a prediction of general relativity, and with ground-based detectors now running in their advanced configuration, we will soon be able to measure them directly for the first time. Binaries of stellar-mass black holes are among the ... More
A rapid evolving region in the Galactic Center: Why S-stars thermalize and more massive stars are missingJan 24 2014Apr 02 2014The existence of "S-stars" within a distance of 1" from SgrA$^*$ contradicts our understanding of star formation, due to the forbiddingly violent environment. A suggested possibility is that they form far and have been brought in by some fast dynamical ... More
Gas in the central region of AGNs: ISM and supermassive gaseous objectsJul 11 2001Jul 16 2001This is a starting point of future work on a more detailed study of early evolutionary phases of galactic nuclei. We put into port the study of the evolution of star accretion onto a supermassive gaseous object in the central region of an active galactic ... More
A realistic spectral function model for charged-current quasielastic-like neutrino and antineutrino cross sections on $^{12}$CDec 22 2018A detailed study of charged current quasielastic neutrino and antineutrino scattering cross sections on a $^{12}$C target with no pions in the final state is presented. The initial nucleus is described by means of a realistic spectral function $S(p,{\cal ... More
Meson-exchange currents and quasielastic predictions for neutrino-nucleus scatteringApr 10 2018We review some recent progress in the study of electroweak interactions in nuclei within the SuSAv2-MEC model. The model has the capability to predict (anti)neutrino scattering observables on different nuclei. The theoretical predictions are compared ... More
Density dependence of 2p-2h meson-exchange currentsApr 05 2017We analyze the density dependence of the contribution of meson-exchange currents to the lepton-nucleus inclusive cross section in the two-particle two-hole channel. The model is based on the Relativistic Fermi Gas, where each nucleus is characterized ... More
The role of meson exchange currents in charged current (anti)neutrino-nucleus scatteringOct 10 2016We present our recent progress in the description of neutrino-nucleus interaction in the GeV region, of interest for ongoing and future oscillation experiments. In particular, we discuss the weak excitation of two-particle-two-hole states induced by meson ... More
Galois Groups in the work of Mira FernandesJan 08 2011In connection to a review of the writings on Galois Theory of the Portuguese mathematician Aureliano Mira Fernandes at turn of the XXth century a brief narrative is presented on how the group theory concepts discovered by Galois are connected to previous ... More
The loss-cone problem in dense nucleiMay 15 2001Jul 18 2001We address the classical problem of star accretion onto a supermassive central gaseous object in a galactic nucleus. The resulting supermassive central gas-star object is assumed to be located at the centre of a dense stellar system for which we use a ... More
Detection of IMBHs with ground-based gravitational wave observatories: A biography of a binary of black holes, from birth to deathOct 01 2009Aug 16 2010Even though the existence of intermediate-mass black holes (IMBHs, black holes with masses ranging between $10^{2-4}\,M_{\odot}$) has not yet been corroborated observationally, these objects are of high interest for astrophysics. Our understanding of ... More
Laser Spectroscopy of Muonic Atoms and IonsSep 12 2016Laser spectroscopy of the Lamb shift (2S-2P energy difference) in light muonic atoms or ions, in which one negative muon $\mu^-$ is bound to a nucleus, has been performed. The measurements yield significantly improved values of the root-mean-square charge ... More
The third data release of the Kilo-Degree Survey and associated data productsMar 08 2017May 21 2017The Kilo-Degree Survey (KiDS) is an ongoing optical wide-field imaging survey with the OmegaCAM camera at the VLT Survey Telescope. It aims to image 1500 square degrees in four filters (ugri). The core science driver is mapping the large-scale matter ... More
Nuclear dependence of the 2p2h electroweak response in the Relativistic Fermi Gas modelJun 27 2017We present the results of a recent study of meson-exchange two-body currents in lepton-nucleus inclusive scattering at various kinematics and for different nuclei within the Relativistic Fermi Gas model. We show that the associated nuclear response functions ... More
Neutrino-Oxygen CC0$π$ scattering in the SuSAv2-MEC modelNov 02 2017Jan 30 2019We present the predictions of the SuSAv2-MEC model for the double differential charged-current muonic neutrino (antineutrino) cross section on water for the T2K neutrino (antineutrino) beam. We validate our model by comparing with the available inclusive ... More
Fast-Decodable Space-Time Codes for the $N$-Relay and Multiple-Access MIMO ChannelDec 03 2014Dec 10 2015In this article, the first general constructions of fast-decodable, more specifically (conditionally) $g$-group decodable, space-time block codes for the Nonorthogonal Amplify and Forward (NAF) Multiple-Input Multiple-Output (MIMO) relay channel under ... More
Nuclear Many-Body Theory of Electroweak Interactions with Nuclei at Intermediate EnergiesAug 03 2004The Quasi-Elastic (QE) contribution of the nuclear inclusive electron model developed in reference \cite{GNO97} is extended to the study of electroweak Charged Current (CC) induced nuclear reactions at intermediate energies of interest for future neutrino ... More
Models of mass segregation at the Galactic centreJun 30 2006We study the process of mass segregation through 2-body relaxation in galactic nuclei with a central massive black hole (MBH). This study has bearing on a variety of astrophysical questions, from the distribution of X-ray binaries at the Galactic centre, ... More
Spin Observables in Coincidence Electron Scattering from Nuclei I: Reduced Response FunctionsJan 26 1998Jan 27 1998A theoretical description of nucleon knockout reactions initiated by polarized electron scattering from polarized nuclei is presented. Explicit expressions for the complete set of reduced response functions (independent of the polarization angle) that ... More
Decoding in Compute-and-Forward Relaying: Real Lattices and the Flatness of Lattice SumsJan 21 2016In a distributed communications scenario, a relay applying the compute-and-forward strategy for the real-valued channel model aims to decode an integer linear combination of transmitted messages, a task of very complex nature for which general efficient ... More
Final-State Interactions in (e,e'p) Reactions with Polarized NucleiNov 09 1998The cross section for coincidence, quasielastic proton knock-out by electrons from a polarized K39 nucleus is computed in DWIA using an optical potential in describing the wave function of the ejected nucleon. The dependence of the FSI on the initial ... More
Tidal disruptions in circumbinary discs (I): Star formation, dynamics, and binary evolutionDec 11 2012In our current interpretation of the hierarchical structure of the universe it is well established that galaxies collide and merge with each other during their lifetime. If massive black holes (MBHs) reside in galactic centres, we expect them to form ... More
What Does Free Space Lambda-Lambda Interaction Predict for Lambda-Lambda Hypernuclei?Oct 18 2001Jun 03 2002Data on Lambda-Lambda hypernuclei provide a unique method to learn details on the strangeness S =-2 sector of the baryon-baryon interaction. From the free space Bonn-Julich potentials, determined from data on baryon-baryon scattering in the S=0,-1 channels, ... More
Quasi-Elastic Neutrino-Nucleus ReactionsFeb 06 2006The quasi-elastic contribution of the nuclear inclusive electron scattering model developed in A. Gil, J. Nieves, and E. Oset: Nucl. Phys. A 627 (1997) 543; is extended to the study of electroweak Charged Current (CC) induced nuclear reactions at intermediate ... More
Higher order moment models of dense stellar systems: Applications to the modeling of the stellar velocity distribution functionJun 07 2010Jul 30 2010Dense stellar systems such as globular clusters, galactic nuclei and nuclear star clusters are ideal loci to study stellar dynamics due to the very high densities reached, usually a million times higher than in the solar neighborhood; they are unique ... More
Geostatistical Rock Physics AVA InversionOct 14 2018Reservoir models are numerical representations of the subsurface petrophysical properties such as porosity, volume of minerals and fluid saturations. These are often derived from elastic models inferred from seismic inversion in a two-step approach: first, ... More
Electron helicity-dependence in (e,e'p) reactions with polarized nuclei and the fifth response functionSep 18 2001The cross section for electron-induced proton knockout reactions with polarized beam and target is computed in a DWIA model. The analysis is focused on the electron helicity-dependent (HD) piece of the cross section. For the case of in-plane emission ... More
Final-State Interaction in Electron Scattering by Polarized NucleiOct 27 1999The cross section for the reaction $^{39}\vec{{\rm K}}(e,e'p)^{38}$Ar is computed, and the dependence of the FSI on the initial polarization angles of the nucleus $^{39}$K is analyzed. The results are explained in a semi-classical picture of the reaction. ... More