Search Publications
A geometric distance measurement to the Galactic center black hole with 0.3% uncertainty
Förster Schreiber, N. M.; Genzel, R.; Sturm, E. +52 more
We present a 0.16% precise and 0.27% accurate determination of R0, the distance to the Galactic center. Our measurement uses the star S2 on its 16-year orbit around the massive black hole Sgr A* that we followed astrometrically and spectroscopically for 27 years. Since 2017, we added near-infrared interferometry with the VLTI beam combi…
Origin of the system of globular clusters in the Milky Way
Massari, D.; Koppelman, H. H.; Helmi, A.
Context. The assembly history experienced by the Milky Way is currently being unveiled thanks to the data provided by the Gaia mission. It is likely that the globular cluster system of our Galaxy has followed a similarly intricate formation path.
Aims: To constrain this formation path, we explore the link between the globular clusters and the…
Stellar and substellar companions of nearby stars from Gaia DR2. Binarity from proper motion anomaly
Mignard, François; Thévenin, Frédéric; Kervella, Pierre +1 more
Context. The census of stellar and substellar companions of nearby stars is largely incomplete, in particular toward the low-mass brown dwarf and long-period exoplanets. It is, however, fundamentally important in the understanding of the stellar and planetary formation and evolution mechanisms. Nearby stars are particularly favorable targets for h…
Gaia-2MASS 3D maps of Galactic interstellar dust within 3 kpc
Arenou, F.; Babusiaux, C.; Katz, D. +5 more
Gaia stellar measurements are currently revolutionizing our knowledge of the evolutionary history of the Milky Way. 3D maps of the interstellar dust provide complementary information and are a tool for a wide range of uses. We built 3D maps of the dust in the Local arm and surrounding regions. To do so, Gaia DR2 photometric data were combined with…
The fourth data release of the Kilo-Degree Survey: ugri imaging and nine-band optical-IR photometry over 1000 square degrees
Sutherland, W.; Heymans, C.; Hoekstra, H. +20 more
Context. The Kilo-Degree Survey (KiDS) is an ongoing optical wide-field imaging survey with the OmegaCAM camera at the VLT Survey Telescope, specifically designed for measuring weak gravitational lensing by galaxies and large-scale structure. When completed it will consist of 1350 square degrees imaged in four filters (ugri).
Aims: Here we pr…
Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18
Khan, S.; Jordi, C.; Anders, F. +19 more
Combining the precise parallaxes and optical photometry delivered by Gaia's second data release with the photometric catalogues of Pan-STARRS1, 2MASS, and AllWISE, we derived Bayesian stellar parameters, distances, and extinctions for 265 million of the 285 million objects brighter than G = 18. Because of the wide wavelength range used, our result…
Gaia Data Release 2. Specific characterisation and validation of all-sky Cepheids and RR Lyrae stars
Szabados, L.; Audard, M.; Rimoldini, L. +21 more
Context. The Gaia second Data Release (DR2) presents a first mapping of full-sky RR Lyrae stars and Cepheids observed by the spacecraft during the initial 22 months of science operations.
Aims: The Specific Objects Study (SOS) pipeline, developed to validate and fully characterise Cepheids and RR Lyrae stars (SOS Cep&RRL) observed by Gaia…
Gaia Data Release 2. Properties and validation of the radial velocities
Smith, M.; Gosset, E.; Allende Prieto, C. +52 more
Context. For Gaia DR2, 280 million spectra collected by the Radial Velocity Spectrometer instrument on board Gaia were processed, and median radial velocities were derived for 9.8 million sources brighter than GRVS = 12 mag.
Aims: This paper describes the validation and properties of the median radial velocities published in Gaia D…
Age determination for 269 Gaia DR2 open clusters
Jordi, C.; Casamiquela, L.; Cantat-Gaudin, T. +9 more
Context. The 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 and test stellar models, paving the way for better understanding of the disk properties.
Aims: The aim of the paper is to improve the knowledge of clu…
Mass and shape of the Milky Way's dark matter halo with globular clusters from Gaia and Hubble
Helmi, Amina; Posti, Lorenzo
Aims: We estimate the mass of the inner (< 20 kpc) Milky Way and the axis ratio of its inner dark matter halo using globular clusters as tracers. At the same time, we constrain the distribution in phase-space of the globular cluster system around the Galaxy.
Methods: We use the Gaia Data Release 2 catalogue of 75 globular clusters' pr…