| Issue |
Astron. Astrophys. Suppl. Ser.
Volume 121, Number 2, February 1997
|
|
|---|---|---|
| Page(s) | 368 - 378 | |
| DOI | https://doi.org/10.1051/aas:1997319 | |
| Published online | 15 February 1997 | |
Long-term monitoring of active stars.*,**
VI. 
observations collected in
Sep.-Oct. 1990
1
Osservatorio Astrofisico di Catania, V.le A.Doria 6, I-95125 Catania, Italy e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
2
Istituto di Rastronomia, C.P. 141, I-96017, Noto (SR), Italy
Send offprint request to: G. Cutispoto
Received:
22
April
1996
Accepted:
6
June
1996
Abstract
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
based on data collected at the European Southern Observatory, La Silla, Chile.
Tables and the complete data set are also available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr or via http://cdsweb.u-strasbg.fr/Abstract.html
© European Southern Observatory (ESO), 1997