Gaia Data Release 2: Properties and validation of the radial velocities

Understand

For Gaia DR2 (GDR2), 280 million spectra, collected by the RVS instrument on-board Gaia, were processed and median radial velocities were derived for 9.8 million sources brighter than Grvs = 12 mag.

• This paper describes the validation and properties of the median radial velocities published in GDR2.
• Quality tests and filters are applied to select, from the 9.8 million radial velocities, those with the quality to be published in GDR2.
• The accuracy of the selected sample is assessed with respect to ground-based catalogues.