A. Vallenari
A5089727038- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Astro and Planetary Science
- Scientific Research and Discoveries
- Adaptive optics and wavefront sensing
- Geophysics and Gravity Measurements
- Galaxies: Formation, Evolution, Phenomena
- Geomagnetism and Paleomagnetism Studies
- Astrophysical Phenomena and Observations
- Distributed and Parallel Computing Systems
- History and Developments in Astronomy
- Atmospheric Ozone and Climate
- Calibration and Measurement Techniques
- Advanced optical system design
- Cosmology and Gravitation Theories
- Modeling, Simulation, and Optimization
- Particle Accelerators and Free-Electron Lasers
- Semiconductor Lasers and Optical Devices
- Spectroscopy and Chemometric Analyses
- Spectroscopy and Laser Applications
- Solar and Space Plasma Dynamics
- Astronomical and nuclear sciences
Osservatorio Astronomico di Padova
2015-2024
University of Oxford
2022
University of Turin
2022
University of Florence
2022
National Institute for Astrophysics
2008-2021
Galaxies, Etoiles, Physique et Instrumentation
2020
Netherlands Institute for Radio Astronomy
2018
Max Planck Society
2018
Brera Astronomical Observatory
2018
University of Padua
1992-2017
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...
Gaia is a cornerstone mission in the science programme of EuropeanSpace Agency (ESA). The spacecraft construction was approved 2006, following study which original interferometric concept changed to direct-imaging approach. Both and payload were built by European industry. involvement scientific community focusses on data processing for international Data Processing Analysis Consortium (DPAC) selected 2007. launched 19 December 2013 arrived at its operating point, second Lagrange point...
We present the early installment of third Gaia data release, EDR3, consisting astrometry and photometry for 1.8 billion sources brighter than magnitude 21, complemented with list radial velocities from DR2. EDR3 contains celestial positions apparent brightness in G approximately sources. For 1.5 those sources, parallaxes, proper motions, (G_BP-G_RP) colour are also available. The passbands G, G_BP, G_RP provided as part release. ease use, 7 million DR2 included this after removal a small...
We present the third data release of European Space Agency's Gaia mission, GDR3. The GDR3 catalogue is outcome processing raw collected with instruments during first 34 months mission by Data Processing and Analysis Consortium. contains same source list, celestial positions, proper motions, parallaxes, broad band photometry in G, G$_{BP}$, G$_{RP}$ pass-bands already Early Third Release. introduces an impressive wealth new products. More than 33 million objects ranges $G_{rvs} < 14$ $3100...
At about 1000 days after the launch of Gaia we present first data release, DR1, consisting astrometry and photometry for over 1 billion sources brighter than magnitude 20.7. We summarize DR1 provide illustrations scientific quality data, followed by a discussion limitations due to preliminary nature this release. consists of: primary astrometric set which contains positions, parallaxes, mean proper motions 2 million brightest stars in common with Hipparcos Tycho-2 catalogues secondary...
Context. Gaia Data Release 2 provides high-precision astrometry and three-band photometry for about 1.3 billion sources over the full sky. The precision, accuracy, homogeneity of both are unprecedented. Aims. We highlight power DR2 in studying many fine structures Hertzsprung-Russell diagram (HRD). allows us to present different HRDs, depending particular on stellar population selections. do not aim here completeness terms types stars or evolutionary aspects. Instead, we have chosen several...
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...
The goal of this paper is to demonstrate the outstanding quality second data release Gaia mission and its power for constraining many different aspects dynamics satellites Milky Way. We focus here on determining proper motions 75 Galactic globular clusters, nine dwarf spheroidal galaxies, one ultra-faint system, Large Small Magellanic Clouds. Using extracted from archive, we derived parallaxes these systems, as well their uncertainties. that errors, statistical systematic, are relatively...
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...
The scientific community needs to be prepared analyse the data from Gaia, one of most ambitious ESA space missions, launched in 2012. purpose this paper is provide and tools order predict advance how Gaia photometry expected be. To do so, we relationships among colours involving magnitudes other commonly used photometric systems (Johnson-Cousins, SDSS, Hipparcos Tycho). up-to-date information industrial partners has been define nominal passbands based on BaSeL3.1 stellar spectral energy...
Context. The third Gaia data release is published in two stages. early part, EDR3, gives very precise astrometric and photometric properties for nearly billion sources together with seven million radial velocities from DR2. full release, DR3, will add velocities, spectra, light curves, astrophysical parameters a large subset of the sources, as well orbits solar system objects. Aims. Before publication catalogue, many different items have undergone dedicated validation processes. goal this...
We produce a clean and well-characterised catalogue of objects within 100\,pc the Sun from \G\ Early Data Release 3. characterise through comparisons to full data release, external catalogues, simulations. carry out first analysis science that is possible with this sample demonstrate its potential best practices for use. The selection used selected training sets, machine-learning procedures, astrometric quantities, solution quality indicators determine probability reliable. set construction...
To illustrate the potential of GDR2, we provide a first look at kinematics Milky Way disc, within radius several kiloparsecs around Sun. We benefit for time from sample 6.4 million F-G-K stars with full 6D phase-space coordinates, precise parallaxes, and Galactic cylindrical velocities . From this sample, extracted sub-sample 3.2 giant to map velocity field disc $\sim$5~kpc $\sim$13~kpc centre up 2~kpc above below plane. also study distribution 0.3 solar neighbourhood ($r < 200$~pc), median...
(Abridged) We have used the atmospheric parameters, [alpha/Fe] abundances and radial velocities, determined from Gaia-ESO Survey GIRAFFE spectra of FGK-type stars (iDR1), to provide a chemo-kinematical characterisation disc stellar populations. focuss on subsample 1016 with high quality covering volume |Z|<4.5kpc R in range 2-13kpc. identified thin thick separation vs [M/H] plane, thanks presence low-density region number density distribution. The seem lie progressively thinner layers...
The Gaia-ESO Survey is obtaining high-quality spectroscopic data for about 10^5 stars using FLAMES at the VLT. UVES high-resolution spectra are being collected 5000 FGK-type stars. These analyzed in parallel by several state-of-the-art methodologies. Our aim to present how these analyses were implemented, discuss their results, and describe a final recommended parameter scale defined. We also precision (method-to-method dispersion) accuracy (biases with respect reference values) of...
Context. For Gaia DR2, 280 million spectra collected by the Radial Velocity Spectrometer instrument on board were processed, and median radial velocities derived for 9.8 sources brighter than G RVS = 12 mag. Aims. This paper describes validation properties of published in DR2. Methods. Quality tests filters applied to select those that have quality be The accuracy selected sample was assessed with respect ground-based catalogues. Its precision estimated using both catalogues distribution...
We present the early installment of third Gaia data release, EDR3, consisting astrometry and photometry for 1.8 billion sources brighter than magnitude 21, complemented with list radial velocities from DR2. EDR3 contains celestial positions apparent brightness in G approximately sources. For 1.5 those sources, parallaxes, proper motions, (G_BP-G_RP) colour are also available. The passbands G, G_BP, G_RP provided as part release. ease use, 7 million DR2 included this after removal a small...
Gaia Data Release 3 (Gaia DR3) contains the second release of combined radial velocities. It is based on spectra collected during first 34 months nominal mission. The longer time baseline and improvements pipeline made it possible to push processing limit, from Grvs = 12 in DR2, 14 mag. In this article, we describe new functionalities implemented for DR3, quality filters applied post-processing properties performance published For several were upgraded or added. (Abridged) DR3 velocities 33...
The Gaia DR3 Catalogue contains for the first time about eight hundred thousand solutions with either orbital elements or trend parameters astrometric, spectroscopic and eclipsing binaries, combinations of them. This paper aims to illustrate huge potential this large non-single star catalogue. Using together models a catalogue tens thousands stellar masses, lower limits, partly consistent flux ratios, has been built. Properties concerning completeness binary catalogues are discussed,...