Kepler-TESS light curve analysis of KIC 10417986 as a practical example for astronomical research in schools

Abstract

Teachers and students in schools have been struggled to accomplish astronomical researches themselves in Thailand, but lacked off equipment and method. The aim of this paper is to provide methods to determine physical parameters of a given Kepler eclipsing binary, without any radial velocity curves, as an example for possible school projects. Unpublished light curves of KIC 10417986 from Kepler and TESS online archives were analysed simultaneously by using the Wilson & Devinney code to derived relative photometric parameters. On an assumption of the system is a contact binary system whose components are main-sequence stars, absolute dimensions including T 1 = 6751 ± 900 K, T 2 = 6804 ± 907 K, R 1 = 1.48 ± 0.05 R⨀, R 2 = 1.4 ± 0.3 R⊙, M1 = 1.64 ± 0.07 M⊙, M2 = 1.6 ± 0.4 M⨀, and L 1 ∼ L 2 ∼ 4L⨀, were determined. The semi-major axis a = 3.7 ± 0.4 R⊙ and a mass ratio q = 1.0 ± 0.2 were calculate tracing backward from the derived dimensions. We found that such a very short period (0d.073731) KIC 10417986 might not play such a good example for school project due to its very low amplitude of variation in light curves (∼0.0007 magnitude) even one may conclude it is not a variable star. However, we found the system interesting since it might have high mass transfer rate from the primary onto the secondary star.