KATZ , D.

At the beginning of the Gaia mission, it will be necessary to calibrate the 3 instruments, and to have data for performance check. A particular scanning mode will be used, allowing quick multiple observations over a small number of sources. This mode and the selection of corresponding sources are described.

Reliable stellar age estimates are fundamental for testing several problems in modern astrophysics, in particular since they set the time scales of Galactic dynamical and chemical evolution. In this study, we determine ages using only Gaia DR3 photometry and parallaxes, in combination with interstellar extinction maps, spectroscopic...

Context. Constraints on the Galactic bulge and bar structures and on their formation history from stellar kinematics and metallicities mainly come from relatively high-latitude fields (|b| > 4 •) where a complex mix of stellar population is seen.Aims. We aim here to constrain the formation history of the Galactic bar by studying the radial...

The Gaia satellite has already provided the astronomical community with three data releases, and the Radial Velocity Spectrometer (RVS) on board Gaia has provided the radial velocity for 33 million stars. When deriving the radial velocity from the RVS spectra, several stars are measured to have large values. To verify the credibility of these...