The Radial Velocity Spectrograph ( RVS ) on board of Gaia needs to be calibrated using stable reference stars known in advance .
The catalogue presented here was built for that purpose .
It includes 1420 radial velocity standard star candidates selected on strict criteria to fulfil the Gaia-RVS requirements .
A large programme of ground-based observations has been underway since 2006 to monitor these stars and verify their stability , which has to be better than 300 m s ^ { -1 } over several years .
The observations were done on the echelle spectrographs ELODIE and SOPHIE on the 1.93-m telescope at Observatoire de Haute-Provence ( OHP ) , NARVAL on the Télescope Bernard Lyot at Observatoire du Pic du Midi and CORALIE on the Euler-Swiss Telescope at La Silla .
Data from the OHP and Geneva Observatory archives have also been retrieved as have HARPS spectra from the ESO archive .
We provide a mean radial velocity in the SOPHIE scale for each star , derived from the combination of velocities measured with those instruments , after having carefully estimated their differences in zero points .
In total , 10214 radial velocity measurements have been obtained for the 1420 stars .
With a mean time baseline of 6.35 years , 92.9 % of the candidates fulfil a target stability criterion of 300 m s ^ { -1 } .
Three hundred forty-three stars are found to be constant at the level of 100 m s ^ { -1 } over 10 years .
Comparisons with earlier catalogues show excellent agreement for FGK stars , with zero-point differences lower than 100 m s ^ { -1 } and a remarkably low RMS scatter of 33 m s ^ { -1 } in one case , suggesting that the precision of the catalogue presented here is better than this value .
This catalogue will likely be useful for other large-scale spectroscopic surveys , such as APOGEE , Gaia-ESO , HERMES , and LAMOST .