New periods of variable stars in Cygnus based on a quarter of century of photographic observations^*

Astronomical Institute of the Slovak Academy of Sciences, 059 60 Tatranská Lomnica, The Slovak Republic e-mail: hric@ta3.sk galis@ta3.sk

Send offprint request to: L. Hric

Received: 13 March 1998
Accepted: 22 September 1998

Abstract

This work summarizes the results of photographic photometry obtained over 24 years at the Skalnaté Pleso (1979-1993) and Asiago (1969-1988) observatories. The period of light changes, the epoch of the maximum or of the minimum, the type of variability and, in some cases, possible causes of the long-term behaviour of light changes were determined for 17 variable stars.