L. Balaguer-Núñez
A5059019834- 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
- Scientific Research and Discoveries
- Geophysics and Gravity Measurements
- Geomagnetism and Paleomagnetism Studies
- Adaptive optics and wavefront sensing
- Galaxies: Formation, Evolution, Phenomena
- Calibration and Measurement Techniques
- Cosmology and Gravitation Theories
- Astronomical and nuclear sciences
- Distributed and Parallel Computing Systems
- Solar and Space Plasma Dynamics
- Atmospheric Ozone and Climate
- Historical Studies in Science
- Earth Systems and Cosmic Evolution
- SAS software applications and methods
- History and Developments in Astronomy
- Pulsars and Gravitational Waves Research
- Inertial Sensor and Navigation
- Archaeological and Historical Studies
- Modeling, Simulation, and Optimization
Universitat de Barcelona
2015-2024
Institut d'Estudis Espacials de Catalunya
2018-2024
Institut Català de Ciències del Clima
2018-2022
Max Planck Society
2018
Centre de Recerca Matemàtica
2009
Thüringer Landessternwarte Tautenburg
2009
University of Vienna
2009
Agencia Estatal de Meteorología
2009
Shanghai Astronomical Observatory
1998-2007
University of Cambridge
2004-2007
Gaia Data Release 2 (Gaia DR2) contains results for 1693 million sources in the magnitude range 3 to 21 based on observations collected by European Space Agency satellite during first 22 months of its operational phase. We describe input data, models, and processing used astrometric content DR2, validation these performed within astrometry task. Some 320 billion centroid positions from pre-processed CCD were estimate five parameters (positions, parallaxes, proper motions) 1332 sources,...
Gaia Early Data Release 3 (Gaia EDR3) contains results for 1.812 billion sources in the magnitude range G = to 21 based on observations collected by European Space Agency satellite during first 34 months of its operational phase. We describe input data, models, and processing used astrometric content EDR3, as well validation these performed within astrometry task. The broadly followed same procedures DR2, but with significant improvements modelling observations. For time data processing,...
Aims. We describe the photometric content of second data release Gaia project (Gaia DR2) and its validation along with quality data. Methods. The was mainly carried out using an internal analysis photometry. External comparisons were also made, but limited by precision systematics that may be present in external catalogues used. Results. In addition to assessment, we best estimates three passbands. Various colour-colour transformations are derived enable users convert between commonly used...
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...
Open clusters are key targets for both Galaxy structure and evolution stellar physics studies. Since \textit{Gaia} DR2 publication, the discovery of undetected has proven that our samples were not complete. Our aim is to exploit Big Data capabilities machine learning detect new open in DR2, complete cluster sample enable further studies on Galactic disc. We use a based methodology systematically search disc, looking overdensities astrometric space identifying them as using photometric...
In the last 15 years different ground-based spectroscopic surveys have been started (and completed) with general aim of delivering stellar parameters and elemental abundances for large samples Galactic stars, complementing Gaia astrometry. Among those surveys, Gaia-ESO Public Spectroscopic Survey (GES), only one performed on a 8m class telescope, was designed to target 100,000 stars using FLAMES ESO VLT (both Giraffe UVES spectrographs), covering all Milky Way populations, special focus open...
WEAVE, the new wide-field, massively multiplexed spectroscopic survey facility for William Herschel Telescope, will see first light in late 2022. WEAVE comprises a 2-degree field-of-view prime-focus corrector system, nearly 1000-multiplex fibre positioner, 20 individually deployable 'mini' integral field units (IFUs), and single large IFU. These systems feed dual-beam spectrograph covering wavelength range 366$-$959\,nm at $R\sim5000$, or two shorter ranges $R\sim20\,000$. After summarising...
The improvements in the precision of published data \textit{Gaia} EDR3 with respect to DR2, particularly for parallaxes and proper motions, offer opportunity increase number known open clusters Milky Way by detecting farther fainter objects that have so far go unnoticed. Our aim is keep completing cluster census detection new stellar groups Galactic disc. We use up magnitude $G = 18$ mag, increasing one unit limit therefore search volume explored our previous studies. \texttt{OCfinder}...
Context. The Gaia-ESO Public Spectroscopic Survey is an ambitious project designed to obtain astrophysical parameters and elemental abundances for 100 000 stars, including large representative samples of the stellar populations in Galaxy, a well-defined sample 60 (plus 20 archive) open clusters. We provide internally consistent results calibrated on benchmark stars star clusters, extending across very wide range ages. This provides legacy data set intrinsic value, equally wide-ranging...
The publication of the Gaia Data Release 2 (Gaia DR2) opens a new era in Astronomy. It includes precise astrometric data (positions, proper motions and parallaxes) for more than $1.3$ billion sources, mostly stars. To analyse such vast amount data, use mining techniques machine learning algorithms are mandatory. search Open Clusters, groups stars that were born move together, located disk, is great example application these techniques. Our aim to develop method automatically explore space,...
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...
The Gaia Data Release 2 (DR2) provided an unprecedented volume of precise astrometric and excellent photometric data. In terms data mining the catalogue, machine learning methods have shown to be a powerful tool, for instance in search unknown stellar structures. Particularly, supervised unsupervised combined together significantly improves detection rate open clusters. We systematically scan DR2 region covering Galactic anticentre Perseus arm $(120 \leq l 205$ $-10 b 10)$, with goal finding...
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...
Context. Chemically inhomogeneous populations are observed in most globular clusters, but not open clusters. Cluster mass seems to play a key role the existence of multiple populations.
Context . The Vela-Puppis region is known to host the Vela OB2 association as well several young clusters featuring OB and pre-main-sequence stars. Several spatial kinematic subgroups have been identified in recent years. Aims By grouping stars based on their positions velocity, we can address question of dynamical history mechanisms that drove stellar formation. Gaia DR2 astrometry photometry enables us characterise 3D distribution estimate ages components. Methods We used an unsupervised...
By far, the color-magnitude diagrams (CMDs) of Galactic open clusters have been considered proto-types single stellar populations. using photometry in ultraviolet and optical bands we discovered that nearby young cluster NGC6705 (M11) exhibits an extended main-sequence turn off (eMSTO) a broadened (MS). This is first evidence multiple populations cluster. high-resolution VLT spectra provide direct sequences along CMD correspond to with different rotation rates. Specifically, blue MS formed...
Context: Open clusters are ideal laboratories to investigate a variety of astrophysical topics, from the properties Galactic disk stellar evolutionary models. Knowing their metallicity and possibly detailed chemical abundances is therefore important. However, number systems with determined high resolution spectroscopy still small.\\ Aims: To increase open radial velocities we used publicly available catalogues surveys in combination Gaia data.\\ Methods: cluster stars have been identified...
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...
Context. Gaia is an ESA cornerstone mission launched on 19 December 2013 aiming to obtain the most complete and precise 3D map of our Galaxy by observing more than one billion sources. This paper part a series documents explaining data processing its results for Data Release 1, focussing G band photometry.