O. Özdarcan

A comprehensive study of the open cluster NGC 6866

We present CCD

High-Level Magnetic Activity on a Low-Mass Close Binary: GSC 02038-0293

UBVRI

Brightness variations in totally eclipsing binary GSC 4589-2999

photometry of the field of the open cluster NGC 6866. Structural parameters of the cluster are determined utilizing the stellar density profile of the stars in the field. We calculate the probabilities of the stars being a physical member of the cluster using their astrometric data and perform further analyses using only the most probable members. The reddening and metallicity of the cluster were determined by independent methods. The LAMOST spectra and the ultraviolet excess of the F and G type main-sequence stars in the cluster indicate that the metallicity of the cluster is about the solar value. We estimated the reddening

The Nature of the Light Variation of the Unique Binary DK CVn

E(B-V)=0.074 \pm 0.050

High-level magnetic activity nature of the eclipsing binary KIC 12418816

mag using the

Spectroscopic and photometric confirmation of chromospheric activity in four stars

U-B

KIC 7385478: An Eclipsing Binary with a γ Doradus Component

vs

V369 Gem : A New Ellipsoidal Variable System with High-level Chromospheric Activity

B-V

Spectroscopic and photometric observations of the selected Algol-type binaries -II. V2080 Cygni and V2365 Ophiuchi

two-colour diagram. The distance modula, the distance and the age of NGC 6866 were derived as

Spectroscopic and photometric observations of the selected Algol-type binaries* -IV. V799 Cassiopeiae, BX Piscium and HD 172189

\mu = 10.60 \pm 0.10