The discovery of six new short-period variables in the old open cluster NGC 188

Abstract

view Abstract Citations (57) References (21) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Discovery of Six New Short-Period Variables in the Old Open Cluster NGC 188 Kaluzny, Janusz ; Shara, Michael M. Abstract The origin and evolution of W UMa contact binaries are controversial. The detection or not of these binaries in open clusters of known age and distance offers important clues about the evolutionary status and absolute elements of W UMa stars. Only in the very old open cluster NGC 188 is more than one W UMa known; in fact, four have been detected. Our CCD survey of this cluster has revealed six new short-period variables, including three contact binaries and a probable FK Comae star. Very accurate coordinates are given for all 10 short-period variables in the cluster, and periods for eight of the 10, and the implications of the apparent richness of this old cluster in contact binaries are discussed. In particular, we may be seeing the entire contact binary evolutionary sequence in one cluster: six normal W UMa stars, one evolved longer period binary, and the FK Comae star. Publication: The Astrophysical Journal Pub Date: March 1987 DOI: 10.1086/165087 Bibcode: 1987ApJ...314..585K Keywords: Binary Stars; Open Clusters; Stellar Evolution; Variable Stars; Astronomical Coordinates; Color-Magnitude Diagram; Light Curve; Power Spectra; Astrophysics; CLUSTERS: OPEN; STARS: VARIABLES; STARS: W URSAE MAJORIS full text sources ADS | data products SIMBAD (14)