A5014011880- Stellar, planetary, and galactic studies
- Astrophysics and Star Formation Studies
- Astronomy and Astrophysical Research
- Astro and Planetary Science
- Astronomical Observations and Instrumentation
- Gamma-ray bursts and supernovae
- Molecular Spectroscopy and Structure
- Astrophysical Phenomena and Observations
- Adaptive optics and wavefront sensing
- Spectroscopy and Laser Applications
- Galaxies: Formation, Evolution, Phenomena
- Space Exploration and Technology
- Scientific Research and Discoveries
- Atmospheric Ozone and Climate
- Advanced Combustion Engine Technologies
- Planetary Science and Exploration
- Calibration and Measurement Techniques
- Historical Astronomy and Related Studies
- Geomagnetism and Paleomagnetism Studies
- Astrophysics and Cosmic Phenomena
- CCD and CMOS Imaging Sensors
- Geophysics and Gravity Measurements
- SAS software applications and methods
- Historical and Architectural Studies
- Solar and Space Plasma Dynamics
Université de Bordeaux
2017-2025
Laboratoire d'Astrophysique de Bordeaux
2017-2025
Institut Universitaire de France
2024-2025
Centre National de la Recherche Scientifique
2017-2024
Centro de Astrobiología
2010-2019
European Space Astronomy Centre
2009-2015
Centre for Astrophysics of the University of Porto
2015
Consejo Superior de Investigaciones Científicas
2006-2014
Instituto de Tecnologías Físicas y de la Información “Leonardo Torres Quevedo”
2010-2014
Instituto Nacional de Técnica Aeroespacial
2011
ABSTRACT Young (125 Myr), populous (>1000 members), and relatively nearby, the Pleiades has provided an anchor for stellar angular momentum models both younger older stars. We used K 2 to explore distribution of rotation periods in Pleiades. With more than 500 new members, we are vastly expanding number with periods, particularly at low-mass end. About 92% members our sample have least one measured spot-modulated period. For ∼8% without non-astrophysical effects often dominate...
The Euclid ERO showcase Euclid's capabilities in advance of its main mission by targeting 17 astronomical objects, including galaxy clusters, nearby galaxies, globular and star-forming regions. A total 24 hours observing time was allocated the early months operation, scientific community engaged through an public data release. We describe development pipeline to create visually compelling images while simultaneously meeting demands within launch leveraging a pragmatic data-driven strategy....
We present HST/WFPC2 observations of a sample 134 ultra-cool objects (spectral types later than M7) coming from the DENIS, 2MASS and SDSS surveys, with distances estimated to range 7 pc 105 pc. Fifteen new binary candidates are reported here. Eleven known binaries confirmed orbital motion is detected in some them. estimate that closest systems this have periods between 5 20 years, thus dynamical masses will be derived near future. For calculation frequency we restrict ourselves less After...
We present extensive early photometric (ultraviolet through near-infrared) and spectroscopic (optical data on supernova (SN) 2008D as well X-ray analysis the associated Swift transient (XRT) 080109. Our span a time range of 5 hr before detection to 150 days after its detection, detailed allowed us derive constraints nature SN progenitor; throughout we draw comparisons with results presented in literature find several key aspects that differ. show spectrum XRT 080109 can be fit equally by an...
We present high-resolution, high dynamic range column-density and color-temperature maps of the Orion complex using a combination Planck dust-emission maps, Herschel 2MASS NIR dust-extinction maps. The combine robustness extinction with resolution coverage constitute highest ever constructed for entire complex, covering 0.01 mag < AK 30 mag, or 2 × 1020 cm-2 N 1023 cm-2. determined ratio 2.2 μm coefficient to 850μm opacity found that values obtained both A B are significantly lower than...
Aims. We study the evolution of circumstellar disks in 22 young (1 to 100 Myr) nearby (within 500 pc) associations over entire mass spectrum using photometry covering from optical mid-infrared.
We use the $\mathit{Gaia}$ DR2 distances of about 700 mid-infrared selected young stellar objects in benchmark giant molecular cloud Orion A to infer its 3D shape and orientation. find that is not fairly straight filamentary we see (2D) projection, but instead a cometary-like oriented toward Galactic plane, with two distinct components: denser enhanced star-forming (bent) Head, lower density star-formation quieter $\sim$75 pc long Tail. The true extent projected $\sim$40 $\sim$90 pc, making...
We study the dependence of protoplanetary disk evolution on stellar mass using a large sample young objects in nearby star-forming regions. update fractions presented our recent work (paper I this series) derived for 22 (< 500 pc) associations between 1 and 100 Myr. use subsample 428 spectroscopically confirmed members to impact evolution. divide into two bins (2 M$_{\odot}$ boundary) age (3 Myr boundary), infrared excesses over photospheric emission classify three groups: disks, evolved...
The Kepler mission has discovered thousands of planet candidates. Currently, some them have already been discarded; more than 200 confirmed by follow-up observations, and several hundreds validated. However, most are still awaiting for confirmation. Thus, priorities (in terms the probability candidate being a real planet) must be established subsequent observations. motivation this work is to provide set isolated (good) host candidates further tested other techniques. We identify close...
The evolution of planetary systems is intimately linked to the their host star. Our understanding whole process based on large planet diversity observed so far. To date, only few tens planets have been discovered orbiting stars ascending Red Giant Branch. Although several theories proposed, question how die remains open due small number statistics. In this work we study giant star Kepler-91 (KOI-2133) in order determine nature a transiting companion. This system was detected by Kepler Space...
Context. The β Pictoris moving group is one of the most well-known young associations in solar neighbourhood and several members are known to host circumstellar discs, planets, comets. Measuring its age precisely essential study astrophysical processes, such as planet formation disc evolution, which strongly age-dependent. Aims. We aim determine a precise accurate dynamical traceback for group. Methods. Our sample combines extremely Gaia DR2 astrometry with ground-based radial velocities...
We investigate the ability of Euclid telescope to detect galaxy-scale gravitational lenses. To do so, we perform a systematic visual inspection $0.7\,\rm{deg}^2$ ERO data towards Perseus cluster using both high-resolution VIS $I_{\scriptscriptstyle\rm E}$ band, and lower resolution NISP bands. inspect every extended source brighter than magnitude $23$ in with $41$ expert human classifiers. This amounts $12\,086$ stamps $10^{\prime\prime}\,\times\,10^{\prime\prime}$. find $3$ grade A $13$ B...
The TW Hydrae Association (TWA) is a young local association (YLA) about 50 pc from the Sun, offering unique opportunity to study star and planet formation processes in detail. We characterized TWA's location, kinematics, age, investigating its origin within Scorpius-Centaurus (Sco-Cen) OB association. Using Gaia DR3 astrometric data precise ground-based radial velocities, we identified substructures TWA, tentatively dividing them into TWA-a TWA-b. Sco-Cen's massive cluster σ Cen (15 Myr,...
AA Tau has been monitored for more than 20 years since 1987, exhibiting a nearly constant brightness level of V=12.5 mag. We report here that in 2011 it suddenly faded away, becoming 2 magnitudes fainter the V-band, and remained this deep state then. new optical near-IR photometry spectroscopy obtained during fading event. The system appears much redder was bright state. Also, 8.2d photometric period continuously observed is not seen most analysis system's colors suggests visual extinction...
The YSOVAR (Young Stellar Object VARiability) Spitzer Space Telescope observing program obtained the first extensive mid-infrared (3.6 & 4.5 um) time-series photometry of Orion Nebula Cluster plus smaller footprints in eleven other star-forming cores (AFGL490, NGC1333, MonR2, GGD 12-15, NGC2264, L1688, Serpens Main, South, IRAS 20050+2720, IC1396A, and Ceph C). There are ~29,000 unique objects with light curves either or both IRAC channels data set. We present collection reduction for...
The aim of this work is to characterize the stellar population between Earth and Orion A molecular cloud where well known star formation benchmark Nebula Cluster (ONC) embedded. We use denser regions block optical background light, effectively isolating in front it. then a multi-wavelength observational approach cloud's foreground population. find that there rich cloud, from B-stars M-stars, with distinct 1) spatial distribution, 2) luminosity function, 3) velocity dispersion reddened inside...
Whilst there is a generally accepted evolutionary scheme for the formation of low-mass stars, analogous processes when moving down in mass to brown dwarfs regime are not yet well understood. In this first paper we try build most complete and unbiased spectroscopically confirmed census population Collinder 69, central cluster Lambda Orionis star forming region, as step addressing question how planetary objects form. We have studied age dependent features optical near-infrared spectra...
We report on Submillimeter Array observations of the 870 μm continuum and CO (3–2), 13CO (2–1), C18O (2–1) line emission a faint object, SMM2E, near driving source HH 797 outflow in IC 348 cluster. The shows an unresolved for which we estimate mass gas dust 30 MJup, (3–2) reveals compact bipolar centred barely seen also (2–1). In addition, hints possible rotating envelope/disc perpendicular to outflow, infer dynamical ∼16 MJup. order further constrain accreted gathered data from Spitzer,...
In the exoplanetary era, Kepler spacecraft is causing a revolution by discovering thousands of new planet candidates. However, follow up program needed in order to reject false candidates and fully characterize bona-fide exoplanets. Our main aims are: 1./ Detect analyze close companions inside typical PSF study if they are responsible dim light curves, 2./ Study change stellar planetary parameters due presence an unresolved object, 3./ Help validate those Objects Interest that do not present...
Filamentary structures are common in molecular clouds. Explaining how they fragment to dense cores is a missing step understanding their role star formation. We perform case study of whether low-mass filaments close-to hydrostatic prior fragmentation, and fragmentation agrees with gravitational models. For this, we the 6.5 pc long Musca cloud that an ideal candidate for filament at early stage fragmentation. employ dust extinction mapping conjunction near-infrared data from NEWFIRM...