2007/07/02 by K. Zloczewski, J. Kaluzny, W. Krzeminski +2 · 8 citations
Physics and Astronomy · Social Sciences · #Astronomy and Astrophysical Research #Blue straggler #Cluster (spacecraft) #Educational Leadership and Practices #Open cluster #Photometry (optics) #Star cluster #Stars #Stellar, planetary, and galactic studies #Subdwarf #Variable star #astro-ph
paper · pdf · doi:10.1111/j.1365-2966.2007.12166.x
published in Monthly Notices of the Royal Astronomical Society 380(3), 1191-1197 (Oxford University Press) · 8 pages, 12 figures, accepted to MNRAS - 29 June 2007
arxiv created 2007/07/02 · openalex publication_date 2007/08/20 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We report the results of photometric monitoring of the Melotte 66 field in BVI filters. 10 variables were identified with nine being new discoveries. The sample includes eight eclipsing binaries of which four are W UMa type stars and one star is a candidate blue straggler. All four contact binaries are likely the members of the cluster based on their estimated distances. 10 blue stars with U−B < −0.3 were detected inside a 14.8 × 22.8 arcmin2 field centred on the cluster. Time series photometry for seven of them showed no evidence for any variability. The brightest object in the sample of blue stars is a promising candidate for a hot subdwarf belonging to the cluster. We show that the anomalously wide main sequence of the cluster, reported in some earlier studies, results from a combination of two effects: variable reddening occurring across the cluster field and the presence of a rich population of binary stars in the cluster itself. The density profile of the cluster field is derived and the total number of the member stars with 16 < V < 21 or 2.8 < MV < 7.8 is estimated conservatively at about 1100.