Related papers: The Gaia DR2 halo white dwarf population: the lumi…
The vast majority of Milky Way stellar halo stars were likely accreted from a small number ($\lesssim$3) of relatively large dwarf galaxy accretion events. However, the timing of these events is poorly constrained, relying predominantly on…
We characterize the Gaia-Enceladus-Sausage kinematic structure recently discovered in the Galactic halo using photometric metallicities from the SkyMapper survey, and kinematics from Gaia radial velocities measurements. By examining the…
We present the kinematics of a sample of 398 DA white dwarfs from the SPY project (ESO SN Ia Progenitor surveY) and discuss kinematic criteria for distinguishing thin-disk, thick-disk, and halo populations. This is the largest homogeneous…
We combine asteroseismology, optical high-resolution spectroscopy, and kinematic analysis for 26 halo red giant branch stars in the \textit{Kepler} field in the range of $-2.5<[\mathrm{{Fe}/{H}}]<-0.6$. After applying theoretically…
Since thin disc stars are younger than thick disc stars on average, the thin disc is predicted by some models to start forming after the thick disc had formed, around 10 Gyr ago. Accordingly, no significant old thin disc population should…
We report the discovery of a nearby, old, halo white dwarf candidate from the Sloan Digital Sky Survey. SDSS J110217.48+411315.4 has a proper motion of 1.75 arcsec/year and redder optical colors than all other known featureless (type DC)…
The recently identified Gaia population of main-sequence--white dwarf (MS+WD) binaries at separations of ${\sim}\,1~{\rm AU}$, often with moderate eccentricities, is not readily reproduced by binary population synthesis models. Barium stars…
The current major challenge to reconstruct the chronology of the Milky Way (MW) is the difficulty to derive precise stellar ages. CMD-fitting offers an alternative to individual age determinations to derive the star formation history (SFH).…
We have carried out a search for massive white dwarfs (WDs) in the direction of young open star clusters using the Gaia DR2 database. The aim of this survey was to provide robust data for new and previously known high-mass WDs regarding…
We determined the age of the stellar content of the Galactic halo by considering main-sequence turn-off stars. From the large number of halo stars provided by Sloan Digital Sky Survey, we could accurately detect the turn-off as a function…
We present the discovery of a white dwarf companion at 3.6" from GJ3346, a nearby ($\pi\sim$42 mas) K star observed with SPHERE@VLT as part of an open time survey for faint companions to objects with significant proper motion discrepancies…
In Papers I and II of this series, the existence of two distinct halo populations of stars have been found in the solar neighborhood. Precise relative ages and orbital parameters are determined for 67 halo and 16 thick-disk stars having…
Since 1996 EROS 2 has surveyed 440 square degrees at high Galactic latitude in order to search for high proper motion stars in the Solar neighbourhood. We present here the analysis of 250 square degrees for which we have three years of…
We present optical spectroscopy and near-infrared photometry of 126 cool white dwarfs in the Sloan Digital Sky Survey (SDSS). Our sample includes high proper motion targets selected using the SDSS and USNO-B astrometry and a dozen…
I report on close encounters of stars to the Sun found in the first Gaia data release (GDR1). Combining Gaia astrometry with radial velocities of around 320 000 stars drawn from various catalogues, I integrate orbits in a Galactic potential…
Gaia Data Release 2 revealed a population of ultramassive white dwarfs on the Q branch that are moving anomalously fast for a local disc population with their young photometric ages. As the velocity dispersion of stars in the local disc…
In very young clusters, stellar age distribution is the empirical proof of the duration of star formation (SF) and of the physical mechanisms involved in the process. We derived accurate stellar ages for the cluster NGC6530, associated with…
The third Gaia Data Release has provided the astronomical community with astrometric data of more than 1.8 billion sources, and low resolution spectra for 220 million. Such a large amount of data is difficult to handle by means of visual…
The Gaia mission has provided an invaluable wealth of astrometric data for more than a billion stars in our Galaxy. The synergy between Gaia astrometry, photometry, and spectroscopic surveys give us comprehensive information about the Milky…
Using a penalised maximum likelihood we estimate, for the first time, the velocity distribution of white dwarfs in the Solar neighbourhood. Our sample consists of 129 675 white dwarfs within 500 pc in Gaia Early Data Release 3 The white…