A5089988303- Stellar, planetary, and galactic studies
- Astronomy and Astrophysical Research
- Astrophysics and Star Formation Studies
- Astro and Planetary Science
- Astronomical Observations and Instrumentation
- Galaxies: Formation, Evolution, Phenomena
- Impact of Light on Environment and Health
- Remote Sensing in Agriculture
- Calibration and Measurement Techniques
- Gamma-ray bursts and supernovae
- Scientific Research and Discoveries
- Inertial Sensor and Navigation
Université de Bordeaux
2018-2022
Centre National de la Recherche Scientifique
2018-2022
Laboratoire d'Astrophysique de Bordeaux
2018-2022
Institut d'Astrophysique de Paris
2018
Sorbonne Université
2018
European Southern Observatory
2016
Uncovering the ingredients and architecture of planetary systems is a very active field research that has fuelled many new theories on giant planet formation, migration, composition, interaction with circumstellar environment. We aim at discovering studying such systems, to further expand our knowledge how low-mass companions form evolve. obtained high-contrast H-band images environment F5V star HD206893, known host debris disc never detected in scattered light. These observations are part...
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...
The large astrometric and photometric survey performed by the Gaia mission allows for a panoptic view of Galactic disc in its stellar cluster population. Hundreds clusters were only discovered after latest G data release (DR2) have yet to be characterised. Here we make use deep homogeneous photometry down G=18 estimate distance, age, interstellar reddening about 2000 identified with Gaia~DR2 astrometry. We these objects study structure evolution disc. rely on set well-determined parameters...
The distribution of member stars in the surroundings an Open Cluster (OC) can shed light on process its formation, evolution and dissolution. analysis structural parameters OCs as a function their age position Galaxy brings constraints theoretical models cluster evolution. Gaia catalogue is very appropriate to find members at large distance from centers. We aim revisiting membership lists solar vicinity, particular by extending these peripheral areas thanks EDR3. used clustering algorithm...
Context. The physical processes driving the formation of Galactic spiral arms are still under debate. Studies using open clusters favour description Milky Way as long-lived structures following classical density wave theory. Current studies comparing Gaia DR2 field stars kinematic information solar neighbourhood to simulations, find a better agreement with short-lived transient behaviour. Aims. Our aim is provide an observational, data-driven view structure and its dynamics main tracers,...
Context. Well studied open clusters (OCs) of the solar neighborhood are frequently used as reference objects to test galactic and stellar theories. For that purpose, their chemical composition needs be known with a high level confidence. It is also important clarify if each OC chemically homogeneous it has unique signature. Aims. The aims this work (1) determine accurate precise abundances 22 species (from Na Eu) in Hyades, Praesepe, Rupecht 147 by using large number stars at different...
Context: Stellar clusters are benchmarks for theories of star formation and evolution. The high precision parallax data the Gaia mission allows significant improvements in distance determination to stellar its stars. In order have accurate precise determinations, systematics like spatial correlations need be accounted for, especially stars small sky regions. Aims: Provide astrophysical community with a free open code designed simultaneously infer cluster parameters (i.e. size) distances...
In the context of large scale structure formation, clusters galaxies are located at nodes cosmic web, and continue to accrete groups along filaments. They show sometimes a very extension preferential direction. Brightest cluster (BCGs) believed grow through accretion many small galaxies, their structural properties expected vary with redshift. some cases BCGs an orientation comparable that which they belong. We analyse morphological 38 from DAFT/FADA CLASH surveys compare position angles...
Context. Open clusters in the process of disruption help to understand formation and evolution Galactic disk. The wealth homogeneity Gaia data have led discovery several open with signs disruption. Detailed chemical information for these is essential order study timescales interplay between star cluster Aims. We perform a morphological, kinematic, analysis disrupting UBC 274 (2.5 Gyr, d = 1778 pc), its global properties. Methods. use HDBSCAN obtain new membership list up 50 pc from centre...
Context: Precise chemical abundances coupled with reliable ages are key ingredients to understand the history of our Galaxy. Open Clusters (OCs) useful for this purpose because they provide good precision. Aims: The aim work is investigate relations different abundance ratios vs age traced by red clump (RC) stars in OCs. Methods: We analyze a large sample 209 members 47 OCs available high-resolution spectroscopy. applied differential line-by-line analysis comprehensive study 25 species. This...
Open Clusters (OCs) are excellent tracers of the formation and evolution Galaxy, as well an ideal laboratory to test theories stellar evolution. In particular, nearby OCs spanning a wide age range commonly used benchmark objects for galactic studies owing highest precision that is achievable. We have designed project perform in-depth study 45 (closer than 500 pc) old (age>300Myr) OCs. After Gaia DR2, very accurate memberships, distances, motions ages available these OCs, allowing us revise...
We use new memberships from Gaia DR2 to investigate the shape of nearest open clusters. their 2D distribution projected on sky and fit two gaussians components central part external envelope. For clusters closer than 200 pc Sun, we 3D ellipsoids spatial members. look for correlations properties with age galactic environment.