An extreme amplitude, massive heartbeat system in the LMC characterized using ASAS-SN and TESS.

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. [ABSTRACT FROM AUTHOR]