Search Publications

Constraining the abundance of dark matter in the central region of the galaxy cluster MACS J1206.2-0847 with a free-form strong lensing analysis

Lam, Daniel; Diego, Jose M.; Herranz, Diego +1 more

We performed a free-form strong lensing analysis of the galaxy cluster MACS J1206.2-0847 in order to estimate and constrain its inner dark matter distribution. The free-form method estimates the cluster total mass distribution without using any prior information about the underlying mass. We used 97 multiple lensed images belonging to 27 backgroun…

Assessing membership projection errors in star forming regions

Cambrésy, L.; Boily, C. M.; Roland, T.

Context. Young stellar clusters harbour complex spatial structures emerging from the star formation process. Identifying stellar over-densities is a key step in better constraining how these structures are formed. The high accuracy of distances derived from Gaia DR2 parallaxes still do not allow us to locate individual stars within clusters of ≈1 …

Using Herschel and Planck observations to delineate the role of magnetic fields in molecular cloud structure (Corrigendum)

Soler, Juan D.

High reddening patches in Gaia DR2. Possible artifacts or indication of star formation at the edge of the Galactic disk

Beitia-Antero, Leire; Gómez de Castro, Ana Inés; de la Fuente Marcos, Raúl

Context. Deep GALEX UV data show that the extreme outskirts of some spiral galaxies are teeming with star formation. Such young stellar populations evolving so far away from the bulk of their host galaxies challenge our overall understanding of how star formation proceeds at galactic scales. It is at present unclear whether our own Milky Way may a…

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…