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Title: An extreme amplitude, massive heartbeat system in the LMC characterized using ASAS-SN and TESS
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 $P_{\rm ASAS-SN}=32.83627\pm 0.00846\, {\rm d},$ and is located towards the LH58 OB complex in the LMC. Both the ASAS-SN and TESS light curves show extreme brightness variations of ${\sim }40{{\ \rm per\ cent}}$ at periastron and variations of $ \sim 10{{\ \rm per\ cent}}$ due to tidally excited oscillations outside periastron. We fit an analytical model of the variability caused by the tidal distortions at pericentre to find orbital parameters of $\omega =-61.4^\circ$, $i=44.8^\circ$, and $e=0.566$. We also present a frequency analysis to identify the pulsation frequencies corresponding to the tidally excited oscillations.  more » « less
Award ID(s):
1908952 1908570
NSF-PAR ID:
10181134
Author(s) / Creator(s):
; ; ; ; ;
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society
Volume:
489
Issue:
4
ISSN:
0035-8711
Page Range / eLocation ID:
4705 to 4711
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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