5 Summary

Figure 4 summarizes the statistics of the survey results. A series of histograms show the distribution of the numerical values of nine activity indicators. Out of the total of 1058 stars observed, 371 (35%) were found with Ca II H&K emission but only 78 (7.3%) with $v\sin i\ge$ 10 kms^-1. On the contrary, a lithium line was detected in 283 (74%) of all stars that had Ca II emission (with 58% of the stars with lithium above 10 mÅ). Out of a subsample of 172 stars with moderate to strong Ca II emission, 168 (97.7%) turned out to be photometric variables and for 134 a photometric (i.e. rotation) period could be obtained. Stellar activity, rotational broadening of spectral lines, and knowledge of a precise stellar rotation period are the key requirements for Doppler imaging. Table 3 lists our new candidates for observation with this technique. Three of the candidates, HD 218153, HD 171488 and HD 291095, were already observed with high-resolution spectroscopy and are currently being Doppler imaged by the authors. In a forthcoming second part of the analysis, we will consider relations between the various activity indicators as deduced from the observations in this paper.

Acknowledgements

KGS is very grateful to the Austrian Fond zur Förderung der wissenschaftlichen Forschung for support through grants S7302-AST (Doppler imaging) and S7301-AST (APT). We all wish to thank NOAO/KPNO for devoting generous amounts of coudé-feed telescope time to fundamental spectroscopy of active stars. We also appreciate numerous discussions with Dr. F.C. Fekel (TSU) regarding our targets and with Dr. J.B. Rice regarding the applicability of the Doppler-imaging technique. This research has made extensive use of the Simbad database, operated at CDS, Strasbourg, France.