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arXiv · 2210.10591

Photometric and spectroscopic studies of the long period low mass ratio deep contact binary KN Per

Xin-Yi Gao·Kai Li·Ya-Wen Cai·Ya-Ni Guo·Xing Gao·Xi Wang·Shi-Peng Yin·Fei Liu·Guo-You Sun
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Abstract

The photometric analysis and spectroscopic study of the long period low mass ratio deep contact binary KN Per were executed. The light curves of BV(RI)$_c$-band were from the Ningbo Bureau of Education and Xinjiang Observatory Telescope (NEXT) at the Xingming Observatory. Through the analysis of Wilson-Devinney (W-D) program, KN Per was found as an A-type low mass ratio deep contact binary (q=0.236, f=53.4\%). A cool spot applied on the primary component was introduced to explain the unequal maxima of the light curve. Based on the O-C analysis, we found that the rate of the increasing orbital period is $\dot{P}$ = 5.12 $\pm$ (0.30) $\times$ 10$^{-7}$ d/yr, meaning the mass transfer from the secondary component to the primary one. By analyzing the spectroscopic data, we detected chromospheric activity emission line indicators, which is corresponding to the light-curve analysis. 71 long period (P $>$ 0.5 days) contact binaries including our target were collected. The evolutionary states of all collected stars were investigated by the illustrations of mass-radius, mass-luminosity, and log M$_{T}$ - log J$_{o}$. The relations of some physical parameters were also determined. With the instability parameters of KN Per, we determined that it is a stable contact binary system at present.

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Xin-Yi Gao, Kai Li, Ya-Wen Cai, Ya-Ni Guo, Xing Gao, Xi Wang, Shi-Peng Yin, Fei Liu, Guo-You Sun. 2022-10-18. Photometric and spectroscopic studies of the long period low mass ratio deep contact binary KN Per. https://doi.org/10.1088/1538-3873%2Fac99fd

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