A. Moitinho
A5106455119- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Astronomical Observations and Instrumentation
- Astro and Planetary Science
- Gamma-ray bursts and supernovae
- Adaptive optics and wavefront sensing
- Advanced optical system design
- Scientific Research and Discoveries
- Galaxies: Formation, Evolution, Phenomena
- Geophysics and Gravity Measurements
- Geomagnetism and Paleomagnetism Studies
- Astrophysical Phenomena and Observations
- Recommender Systems and Techniques
- History and Developments in Astronomy
- Advanced Text Analysis Techniques
- Biomedical Text Mining and Ontologies
- Calibration and Measurement Techniques
- Machine Learning in Materials Science
- Computational Drug Discovery Methods
- Pulsars and Gravitational Waves Research
- Astronomical and nuclear sciences
- Atmospheric Ozone and Climate
- Algorithms and Data Compression
- Topic Modeling
University of Lisbon
2015-2024
Weatherford College
2020
Max Planck Society
2018
European Space Astronomy Centre
2018
Uninova
2015
Lusíada University of Lisbon
2010
Institute of Astrophysics and Space Sciences
2005-2008
Max Planck Institute for Radio Astronomy
2008
Institut de Planétologie et d'Astrophysique de Grenoble
2008
Centre National de la Recherche Scientifique
2008
Context. We present the second Gaia data release, DR2, consisting of astrometry, photometry, radial velocities, and information on astrophysical parameters variability, for sources brighter than magnitude 21. In addition epoch astrometry photometry are provided a modest sample minor planets in solar system. Aims. A summary contents DR2 is presented, accompanied by discussion differences with respect to DR1 an overview main limitations which still survey. Recommendations made responsible use...
We have compiled a new catalogue of open clusters in the Galaxy which updates previous catalogues Lyngå ([CITE]) and Mermilliod (included WEBDA database). New objects data, particular, data on kinematics (proper motions) that were not present old catalogues, been included. Virtually all (1537) presently known included, represents an increment about 347 relative to catalogue. The is presented single table containing important makes it easy use. can be accessed line either at...
Open clusters are convenient probes of the structure and history Galactic disk. They also fundamental to stellar evolution studies. The second Gaia data release contains precise astrometry at sub-milliarcsecond level homogeneous photometry mmag level, that can be used characterise a large number over entire sky. In this study we aim establish list members derive mean parameters, in particular distances, for as many possible, making use alone. We compile thousands known or putative from...
Context. The second Gaia data release (DR2) contains very precise astrometric and photometric properties for more than one billion sources, astrophysical parameters dozens of millions, radial velocities variability information half a million stars from selected classes, orbits thousands solar system objects. Aims. Before the catalogue was published, these have undergone dedicated validation processes. goal this paper is to describe results in terms completeness, accuracy, precision various...
Before the publication of Gaia Catalogue, contents first data release have undergone multiple dedicated validation tests. These tests aim at analysing in-depth Catalogue content to detect anomalies, individual problems in specific objects or overall statistical properties, either filter them before public release, describe different caveats for an optimal exploitation data. Dedicated methods using internal data, external catalogues models been developed processes. They are testing normal...
In this study we follow up our recent paper (Monteiro et al. 2020) and present a homogeneous sample of fundamental parameters open clusters in Galaxy, entirely based on Gaia DR2 data. We used published membership probability the stars derived from data applied isochrone fitting code, updated as Monteiro (2020), to GB GR for member stars. doing take into account nominal errors derive distance, age, extinction each cluster. This work therefore provides 1743 and, byproduct, list likely not...
ESPRESSO, the Echelle SPectrograph for Rocky Exoplanets and Stable Spectroscopic Observations, will combine efficiency of modern echelle spectrograph design with extreme radial-velocity precision. It be installed on ESO's VLT in order to achieve a gain two magnitudes respect its predecessor HARPS, instrumental radialvelocity precision improved reach cm/s level. Thanks characteristics ability combining incoherently light 4 large telescopes, ESPRESSO offer new possibilities various fields...
Aims. We develop a method for membership assignment in stellar clusters using only photometry and positions. The is aimed to be unsupervised, data driven, model free, rely on as few assumptions possible.
Context. Open clusters are very good tracers of the evolution Galactic disc. Thanks to Gaia, their kinematics can be investigated with an unprecedented precision and accuracy. Aims. The distribution open in 6D phase space is revisited Gaia DR2. Methods. weighted mean radial velocity was determined, using most probable members available from a previous astrometric investigation that also provided parallaxes proper motions. Those parameters, all derived DR2 only, were combined provide...
Young massive clusters (YMCs) with stellar masses of 104–105 M☉ and core densities stars per cubic pc are thought to be the "missing link" between open extreme extragalactic super star globular clusters. As such, studying initial conditions YMCs offers an opportunity test cluster formation models across full mass range. G0.253 + 0.016 is excellent candidate YMC progenitor. We make use existing multi-wavelength data including recently available far-IR continuum (Herschel/Herschel Infrared...
We use the $\mathit{Gaia}$ DR2 distances of about 700 mid-infrared selected young stellar objects in benchmark giant molecular cloud Orion A to infer its 3D shape and orientation. find that is not fairly straight filamentary we see (2D) projection, but instead a cometary-like oriented toward Galactic plane, with two distinct components: denser enhanced star-forming (bent) Head, lower density star-formation quieter $\sim$75 pc long Tail. The true extent projected $\sim$40 $\sim$90 pc, making...
The Gaia Data Release 2 contains the 1st release of radial velocities complementing kinematic data a sample about 7 million relatively bright, late-type stars. Aims: This paper provides detailed description spectroscopic processing pipeline, and approach adopted to derive presented in DR2. Methods: pipeline must perform four main tasks: (i) clean reduce spectra observed with Radial Velocity Spectrometer (RVS); (ii) calibrate RVS instrument, including wavelength, straylight, line-spread...
Context. Open clusters (OCs) are popular tracers of the structure and evolutionary history Galactic disc. The OC population is often considered to be complete within 1.8 kpc Sun. recent Gaia Data Release 2 (DR2) allows latter claim challenged. Aims. We perform a systematic search for new OCs in direction Perseus using precise accurate astrometry from DR2. Methods. implemented coarse-to-fine method. First, we exploited spatial proximity fast density-aware partitioning sky via k -d tree domain...
Open Clusters (OCs) can trace with a great accuracy the evolution of Galactic disk. The aim this work is to study kinematical behavior OC population over time. We take advantage latest age determinations OCs investigate correlations 6D phase space coordinates and orbital properties age. also rotation curve Milky Way traced by we compare it that other observational or theoretical studies. gathered nearly 30000 Radial Velocity (RV) measurements members from both Gaia-RVS data ground based...
$Context$. Gaia Second Data Release provides precise astrometry and photometry for more than 1.3 billion sources. This catalog opens a new era concerning the characterization of open clusters test stellar models, paving way better understanding disc properties. $Aims$. The aim paper is to improve knowledge cluster parameters, using only unprecedented quality astrometry. $Methods$. We make use membership determination based on photometry. apply anautomated Bayesian tool, BASE-9, fit...
The Gaia Data Release 2 (DR2): we summarise the processing and results of identification variable source candidates RR Lyrae stars, Cepheids, long period variables (LPVs), rotation modulation (BY Dra-type) delta Scuti & SX Phoenicis short-timescale variables. In this release aim to provide useful but not necessarily complete samples candidates. processed data consist G, BP, RP photometry during first 22 months operations as well positions parallaxes. Various methods from classical...
The large astrometric and photometric survey performed by the Gaia mission allows for a panoptic view of Galactic disc in its stellar cluster population. Hundreds clusters were only discovered after latest G data release (DR2) have yet to be characterised. Here we make use deep homogeneous photometry down G=18 estimate distance, age, interstellar reddening about 2000 identified with Gaia~DR2 astrometry. We these objects study structure evolution disc. rely on set well-determined parameters...
The Tycho-Gaia Astrometric Solution (TGAS) subset of the first Gaia catalogue contains an unprecedented sample proper motions and parallaxes for two million stars brighter than G~12 mag. We take advantage full astrometric solution available those to identify members known open clusters compute mean cluster parameters using either TGAS or UCAC4 motions, parallaxes. apply unsupervised membership assignment procedure select high probability members, we use a Bayesian/MCMC technique fit stellar...
Reliable fundamental parameters of open clusters such as distance, age and extinction are key to our understanding Galactic structure stellar evolution. In this work we use {\it Gaia} DR2 investigate 45 listed in the \emph{New catalogue optically visible candidates} (DAML) but with no previous astrometric membership estimation based on DR2. process selecting targets for study found that some reported new discoveries recent papers were already known DAML. Cluster memberships determined using...
Aims. We present pyUPMASK, an unsupervised clustering method for stellar clusters that builds upon the original UPMASK package. Its general approach makes it plausible to be applied analyses deal with binary classes of any kind, as long fundamental hypotheses are met. The code is written entirely in Python and made available through a public repository. Methods.The core algorithm follows developed but introducing several key enhancements. These enhancements not only make pyUPMASK more...
We combine optical and radio observations to trace the spiral structure in third quadrant of Milky Way. The consist a large sample young open clusters associations, whereas survey nearby distant clouds observed CO. Both samples are largest ones thus far presented literature. use this unique material analyze behavior interstellar extinction detailed Galactic (TGQ).We find that outer (Cygnus) grand design arm is traced by stellar CO components, while Perseus solely possibly being disrupted...
Orion A hosts the nearest massive star factory, thus offering a unique opportunity to resolve processes connected with formation of both low- and high-mass stars. Here we present most detailed sensitive near-infrared (NIR) observations entire molecular cloud date. With combination high image quality, survey coverage, sensitivity, our NIR aims at establishing solid empirical foundation for further studies this important cloud. In first paper observations, data reduction, source catalog...
In the context of ESA M5 (medium mission) call we proposed a new satellite mission, Theia, based on relative astrometry and extreme precision to study motion very faint objects in Universe. Theia is primarily designed local dark matter properties, existence Earth-like exoplanets our nearest star systems physics compact objects. Furthermore, about 15 $\%$ mission time was dedicated an open observatory for wider community propose complementary science cases. With its unique metrology system...