Radial velocities of Hipparcos southern B8-F2 type stars

Radial velocities have been determined for a sample of B8-F2 type stars obs erved by the Hipparcos satellite. Observations were obtained within the fra mework of an ESO key-program. Radial velocities have been measured using a cross-correlation method, the templates being a grid of synthetic spectra. The obtained precision depends on effective temperature and projected rotat ional velocity of the star as well as on a possible asymmetry of the correl ation peak generally due to secondary components. New spectroscopic binarie s have been detected from these asymmetries and the variability of the meas ured radial velocity. Simulations of binary and triple systems have been pe rformed. For binaries our results have been compared with Hipparcos binary data. Adding the variable radial velocities, the minimum binary fraction ha s been found 60% for physical systems. Radial velocities have been determin ed for 581 B8-F2 stars, 159 being new. Taking into account published radial velocities, 39% south A-type stars with V magnitude lower than 7.5 have a radial velocity.