The Physical Properties and Starspot Activity of the Triple System KIC 6525196

Abstract

We present the results of photometric and spectroscopic analysis for the triplelined system KIC 6525196, an eclipsing binary accompanied by a third star. By modeling the Kepler light curves and radial velocities from LAMOST and HIDES observations, absolute parameters of the system are determined. Both components of the eclipsing binary are found to be solar-like stars with masses and radii of M1 = 1.0286 ± 0.0026M⊙, R1 = 1.127 ± 0.008R⊙, and M2 = 0.9667 ± 0.0024M⊙, R2 = 0.963 ± 0.007R⊙. The mass of the third star is determined to be M3 = 0.772 ± 0.010M⊙. With the out-of-eclipse light residuals, we measure rotation period and decay timescale of active region by using the autocorrelation function. In comparison to the Sun, the activity level of the system is significantly stronger. In addition, a possible short photometric activity cycle of ∼ 244 days is detected.

KIC 7284688: A Solar-type Eclipsing Binary with Rapidly Varying O’Connell Effect

“…Due to RV zero-points of standard stars vary between exposures in LAMOST Medium-resolution Survey (Zhang et al 2021;Pan et al 2022), similar to differential photometry, we apply differential radial velocity to correct zero-point offset among RVs. Two candidates of RV standard stars with standard deviations of absolute RVs less than 1.0 km s −1 from Zhang et al (2021) are selected as the comparison (α J2000.0 = 292°.1127, δ J2000.0 = 43°.…”