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arXiv · 1901.00005

An Extreme Amplitude, Massive Heartbeat System in the LMC Characterized Using ASAS-SN and TESS

T. Jayasinghe·K. Z. Stanek·C. S. Kochanek·Todd A. Thompson·B. J. Shappee·M. Fausnaugh
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Abstract

Using ASAS-SN data, we find that the bright ($V{\sim}13.5$ mag) variable star MACHO 80.7443.1718 (ASASSN-V J052624.38-684705.6) is the most extreme heartbeat star yet discovered. This massive binary, consisting of at least one early B-type star, has an orbital period of $P_{\rm ASAS-SN}=32.83627\pm0.00846\,{\rm d},$ and is located towards the LH58 OB complex in the LMC. Both the ASAS-SN and TESS light curves show extreme brightness variations of ${\sim}40\%$ at periastron and variations of ${\sim}10\%$ due to tidally excited oscillations outside periastron. We fit an analytical model of the variability caused by the tidal distortions at pericenter to find orbital parameters of $ω=-61.4$ deg, $i=44.8$ deg and $e=0.566$. We also present a frequency analysis to identify the pulsation frequencies corresponding to the tidally excited oscillations.

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T. Jayasinghe, K. Z. Stanek, C. S. Kochanek, Todd A. Thompson, B. J. Shappee, M. Fausnaugh. 2021-02-23. An Extreme Amplitude, Massive Heartbeat System in the LMC Characterized Using ASAS-SN and TESS. https://doi.org/10.1093/mnras%2Fstz2460

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