5 Conclusion

Radial velocities have been determined for 581 B8 to F2 stars, 159 being new. A detailed analysis of the A0 type stars for a detailed study of the HR-diagram (Gerbaldi et al. 1998) confirms the important percentage of binaries. The determination of vsini has been made by Fourier transform and will be published soon (Royer et al.). A systematic comparison between his values and the rotation broadening of the adopted synthetic spectrum for each star shows that some of the stars with large vsini are multiple systems in fact, and it confirms the preliminary results obtained with the Elodie spectrometer at the Haute Provence Observatory (Grenier et al.).

Acknowledgements

We would like to thank ESO staff members and night assistance of La Silla for their skillfulness and for their kindness.