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arXiv · 1611.01684

Chromospherically Active Low-Mass Close Binary: KIC 9761199

Ezgi Yoldas·Hasan Ali Dal
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Abstract

In this study, we present the results obtained from KIC 9761199's the photometrical data acquired by the Kepler Mission. The light curve of the system, the sinusoidal variation out-of-eclipses and instant-short term flare events in the entire light curves were analyzed. The temperature of the secondary component was found to be 3891+-1 K, while the mass ratio of the components (q) was found to be 0.69+-0.01, and the orbital inclination (i) was computed as 77.4+-0.1 degrees. The sinusoidal variation is caused by the stellar spots of two active regions separated by about 180 degrees longitudinally located around the latitudes of +47 and +30 degrees. In addition, 94 flares were detected and their parameters were computed. The OPEA model was derived for these flares and its parameters were computed. The Plateau value as saturation level for the active component was found to be 1.951+-0.069 s, while the half-life value was found to be 1014 s. The flare frequency N1 was found to be 0.01351 per hour, while the flare frequency N2 was found to be 0.00006. Maximum flare rise time (Tr) was found to be 1118.098 s, while maximum flare total time (Tt) was found to be 6767.72 s. Comparing its analogue it is seen that the chromospheric activity level of KIC 9761199, which is a low-mass close binary system according to the light curve analyses, is an expected level according to the (B-V) color index of 1.303 mag for the active component.

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Ezgi Yoldas, Hasan Ali Dal. 2016-11-05. Chromospherically Active Low-Mass Close Binary: KIC 9761199. https://arxiv.org/abs/1611.01684

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