Astron. Astrophys. Suppl. Ser.
Volume 121, Number 2, February 1997
|Page(s)||368 - 378|
|Published online||15 February 1997|
VI. observations collected in Sep.-Oct. 1990
Osservatorio Astrofisico di Catania, V.le A.Doria 6, I-95125 Catania, Italy e-mail: firstname.lastname@example.org
2 Istituto di Rastronomia, C.P. 141, I-96017, Noto (SR), Italy
Send offprint request to: G. Cutispoto
Accepted: 6 June 1996
In the framework of an extensive program focusing on the global properties and evolution of active stars, high-precision photometry of 9 selected stars, collected at the European Southern Observatory over the intervals 7-17 September and 30 September - 10 October 1990, is presented. Significant evolution of the light curves, period variations and evidence for long-term variability of the global degree of spottedness are found. Some of the spectral classifications are discussed. These observations contribute to the establishment of a time-extended photometric database which can give important clues on topics such as the stability of the spotted areas, differential rotation, solar-like cycles and the correlation between inhomogeneities at different atmospheric levels.
Key words: stars: activity / stars: late-type / stars: variables
© European Southern Observatory (ESO), 1997