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arXiv · 2401.15986

Physical Parameters of 11,100 Short-Period ASAS-SN Eclipsing Contact Binaries

Xu-Zhi Li·Qing-Feng Zhu·Xu Ding·Xiao-Hui Xu·Hang Zheng·Jin-Sheng Qiu·Ming-Chao Liu
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Abstract

Starting from more than 11,200 short-period (less than 0.5 days) EW-type eclipsing binary candidates with the All-Sky Automated Survey for Supernovae (ASAS-SN) V-band light curves, we use MCMC and neural networks (NNs) to obtain the mass ratio ($q$), orbital inclination ($incl$), fill-out factor ($f$) and temperature ratio ($T_s/T_p$). After cross-matching with the Gaia DR3 database, the final sample contains parameters of 2,399 A-type and 8,712 W-type contact binaries (CBs). We present the distributions of parameters of these 11,111 short-period CBs. The mass ratio ($q$) and fill-out factor ($f$) are found to obey log-normal distributions, and the remaining parameters obey normal distributions. There is a significant period-temperature correlation of these CBs. Additionally, the temperature ratio (${T_s}$/${T_p}$) tends to increase as the orbital period decreases for W-type CBs. There is no significant correlation between them for A-type CBs. The mass ratio and fill-out factor ($q-f$) diagram suggest there is no significant correlation between these two parameters. A clear correlation exists between the mass ratio and radius ratio. The radius ratio increases with the mass ratio. Moreover, the deep fill-out CBs tend to fall on the upper boundary of the $q$$-$${R_s}$/${R_p}$ distribution, while the shallow fill-out CBs fall on the lower boundary.

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Xu-Zhi Li, Qing-Feng Zhu, Xu Ding, Xiao-Hui Xu, Hang Zheng, Jin-Sheng Qiu, Ming-Chao Liu. 2024-01-29. Physical Parameters of 11,100 Short-Period ASAS-SN Eclipsing Contact Binaries. https://arxiv.org/abs/2401.15986

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