Variable stars in the field of open cluster NGC 6939
Loading...
Date
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Description
The results of CCD photometric survey performed with the 90/180 cm Schmidt-Cassegrain Telescope of the Nicolaus Copernicus University Astronomical Observatory in Piwnice (Poland) and the 70/172 cm Schmidt Telescope of the National Astronomical Observatory (NAO) at Rozhen (Bulgaria) of the field of 1 Gyr old open cluster NGC 6939 are presented. Twenty two variable stars were detected, four of them previously known. Four eclipsing systems (3 detached and 1 contact binary) were found to be members of the cluster. Analysis of the brightness of the contact binary V20 strongly supports the distance to the cluster of 1.74 +/- 0.20 kpc. The small population of contact binaries in NGC 6939 confirms also the relatively young age of the cluster.
9 pages, 3 figures, accepted for publication in AN
9 pages, 3 figures, accepted for publication in AN