J. L. Halbwachs
A5032864089- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astronomical Observations and Instrumentation
- Astro and Planetary Science
- Astrophysics and Star Formation Studies
- History and Developments in Astronomy
- Gamma-ray bursts and supernovae
- Geophysics and Gravity Measurements
- Historical Astronomy and Related Studies
- Scientific Research and Discoveries
- Geomagnetism and Paleomagnetism Studies
- Adaptive optics and wavefront sensing
- Solar and Space Plasma Dynamics
- Inorganic Fluorides and Related Compounds
- French Historical and Cultural Studies
- Galaxies: Formation, Evolution, Phenomena
- Historical Geography and Cartography
- Spacecraft and Cryogenic Technologies
- Astronomical and nuclear sciences
- Superconducting Materials and Applications
- Nuclear physics research studies
- Nuclear Physics and Applications
- Planetary Science and Exploration
- Library Science and Information Systems
- Methane Hydrates and Related Phenomena
Observatoire astronomique de Strasbourg
2012-2022
Université de Strasbourg
1994-2022
Centre National de la Recherche Scientifique
2002-2022
Max Planck Society
2018
Institut Laue-Langevin
2017
University of Antwerp
1992
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 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...
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...
Wide binaries are tracers of the gravity field Galaxy, but their study requires some caution. A large list common proper motion stars selected from third Astronomischen Gesellschaft Katalog (AGK3) was monitored with CORAVEL (for COrrelation RAdial VELocities) spectrovelocimeter, in order to prepare a sample physical very wide separations. 66 received special attention, since radial velocities (RV) seemed be variable. These were over several years derive elements spectroscopic orbits. In...
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...
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,...
With the most recent Gaia data release number of sources with complete 6D phase space information (position and velocity) has increased to well over 33 million stars, while stellar astrophysical parameters are provided for more than 470 sources, in addition identification 11 variable stars. Using variability classifications DR3, we select various populations explore identify non-axisymmetric features disc Milky Way both configuration velocity space. about 580 thousand identified as hot OB...
Context.The Gaia Early Data Release 3 contained the positions, parallaxes and proper motions of 1.5 billion sources, among which some did not fit well "single star" model. Binarity is one causes this. Aims. Four million these stars were selected various models tested to detect binary derive their parameters. Methods. A preliminary treatment was used discard partially resolved double correct transits for perspective acceleration. It then investigated whether measurements with an acceleration...
Two CORAVEL radial velocity surveys – one among stars in the solar neighbourhood, other Pleiades and Praesepe are merged to derive statistical properties of main–sequence binaries with spectral types F7 K periods up 10 years. A sample 89 spectroscopic orbits was finally obtained. Among them, 52 relate a free–of–bias selection 405 (240 field 165 cluster stars). The statistics corrected for effects yield following results: (1) No discrepancy is found between open cluster. distributions mass...
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...
We compare the Gaia DR2 and EDR3 performances in study of Magellanic Clouds show clear improvements precision accuracy new release. also that systematics still present data make determination 3D geometry LMC a difficult endeavour; this is at very limit usefulness astrometry, but it may become feasible with use additional external data. derive radial tangential velocity maps global profiles for several subsamples we defined. To our knowledge, first time two planar components ordered random...
Context. Gaia Early Data Release 3 (Gaia EDR3) provides accurate astrometry for about 1.6 million compact (QSO-like) extragalactic sources, 1.2 of which have the best-quality five-parameter astrometric solutions. Aims. The proper motions QSO-like sources are used to reveal a systematic pattern due acceleration solar system barycentre with respect rest frame Universe. Apart from being an important scientific result by itself, measured in this way is good quality indicator solution. Methods....
Context. The first Gaia Data Release contains the Tycho-Gaia Astrometric Solution (TGAS). This is a subset of about 2 million stars for which, besides position and photometry, proper motion parallax are calculated using Hipparcos Tycho-2 positions in 1991.25 as prior information. Aims. We investigate scientific potential limitations TGAS component by means astrometric data open clusters. Methods. Mean cluster values derived taking into account error correlations within solutions individual...
The Gaia spacecraft of the European Space Agency (ESA) has been securing observations solar system objects (SSOs) since beginning its operations. Data Release 2 (DR2) contains a selected sample 14,099 SSOs. These asteroids have already identified and numbered by Minor Planet Center. Positions are provided for each observation at CCD level. As additional information, apparent brightness SSOs in unfiltered G band is also observations. We explain processing SSO data, describe criteria we used...
We aim to demonstrate the scientific potential of Gaia Early Data Release 3 (EDR3) for study Milky Way structure and evolution. used astrometric positions, proper motions, parallaxes, photometry from EDR3 select different populations components calculate distances velocities in direction anticentre. explore disturbances current disc, spatial kinematical distributions early accreted versus in-situ stars, structures outer parts orbits open clusters Berkeley 29 Saurer 1. find that: i) dynamics...
The Gaia Galactic survey mission is designed and optimized to obtain astrometry, photometry, spectroscopy of nearly two billion stars in our Galaxy. Yet as an all-sky multi-epoch survey, also observes several million extragalactic objects down a magnitude G~21 mag. Due the nature onboard selection algorithms, these are mostly point-source-like objects. Using data provided by satellite, we have identified quasar galaxy candidates via supervised machine learning methods, estimate their...
The ESA Gaia mission provides a unique time-domain survey for more than 1.6 billion sources with G ~ 21 mag. We showcase stellar variability across the Galactic colour-absolute magnitude diagram (CaMD), focusing on pulsating, eruptive, and cataclysmic variables, as well stars exhibiting due to rotation eclipses. illustrate locations of variable star classes, object fractions, typical amplitudes throughout CaMD how variability-related changes in colour brightness induce `motions' using 22...