摘要
Photometric observations in Sloan 9＇ and i＇ bands of four W UMa stars, NSVS 2244206, NSVS 908513, CSS J004004.7＋385531 and VSX J062624.4＋570907, are presented. The light curve solutions reveal that all targets have overcontact configurations with fillout factors within 0.15-0.26. Their components are G-K spectral types and are almost in thermal contact. They are also relatively close in size and luminosity： the radius ratios r2/r1 are within 0.75-0.90; the luminosity ratios 12/11 are within 0.53-0.63. The results of the light curve solution of CSS J004004.7＋385531 imply the weak limb-darkening effect of its primary component and possible presence of additional absorbing features in the system.
Photometric observations in Sloan 9＇ and i＇ bands of four W UMa stars, NSVS 2244206, NSVS 908513, CSS J004004.7＋385531 and VSX J062624.4＋570907, are presented. The light curve solutions reveal that all targets have overcontact configurations with fillout factors within 0.15-0.26. Their components are G-K spectral types and are almost in thermal contact. They are also relatively close in size and luminosity： the radius ratios r2/r1 are within 0.75-0.90; the luminosity ratios 12/11 are within 0.53-0.63. The results of the light curve solution of CSS J004004.7＋385531 imply the weak limb-darkening effect of its primary component and possible presence of additional absorbing features in the system.
基金
supported partly by funds of project RD 08-244 of Scientific Foundation of Shumen University
the AAVSO Photometric All-Sky Survey(APASS),funded by the Robert Martin Ayers Sciences Fund
