We characterize the extreme heartbeat star system MACHO 80.7443.1718 in the Large Magellanic Cloud using Transiting Exoplanet Survey Satellite (TESS) photometry and spectroscopic observations from the Magellan Inamori Kyocera Echelle (MIKE) and SOAR Goodman spectographs. MACHO 80.7443.1718 was first identified as a heartbeat star system in the All-Sky Automated Survey for SuperNovae (ASAS-SN) with $P_{\rm orb}=32.836\pm 0.008\, {\rm d}$. MACHO 80.7443.1718 is a young (∼6 Myr), massive binary, composed of a B0 Iae supergiant with $M_1 \simeq 35\, {\rm M}_\odot$ and an O9.5V secondary with $M_2 \simeq 16\, {\rm M}_\odot$ on an eccentric (e = 0.51 ± 0.03) orbit. In addition to having the largest variability amplitude amongst all known heartbeats stars, MACHO 80.7443.1718 is also one of the most massive heartbeat stars yet discovered. The B[e] supergiant has Balmer emission lines and permitted/forbidden metallic emission lines associated with a circumstellar disc. The disc rapidly dissipates at periastron that could indicate mass transfer to the secondary, but re-emerges immediately following periastron passage. MACHO 80.7443.1718 also shows tidally excited oscillations at the N = 25 and N = 41 orbital harmonics and has a rotational period of 4.4 d.

中文翻译：

---

最响亮的恒星心跳：表征最极端振幅的心跳恒星系统

我们使用凌日系外行星测量卫星 (TESS) 光度测量和来自麦哲伦稻盛京瓷阶梯 (MIKE) 和 SOAR Goodman 光谱仪的光谱观测来表征大麦哲伦云中的极端心跳恒星系统 MACHO 80.7443.1718。MACHO 80.7443.1718 在超新星全天自动巡天 (ASAS-SN) 中首次被确定为心跳星系统，$P_{\rm orb}=32.836\pm 0.008\, {\rm d}$。MACHO 80.7443.1718 是一个年轻的（~6 Myr）大质量双星，由一个具有 $M_1 \simeq 35\、{\rm M}_\odot$ 的 B0 Iae 超巨星和一个具有 $M_2 \simeq 的 O9.5V 次级星组成16\, {\rm M}_\odot$ 在偏心 (e = 0.51 ± 0.03) 轨道上。MACHO 80.7443.1718 除了在所有已知的心跳星中具有最大的变异幅度外，它也是迄今为止发现的最大质量的心跳星之一。B[e] 超巨星有 Balmer 发射线和与一个环星盘相关的允许/禁止的金属发射线。圆盘在近星点处迅速消散，这可能表明质量转移到次级，但在近星点通过后立即重新出现。MACHO 80.7443.1718 还显示了 N = 25 和 N = 41 轨道谐波的潮汐激发振荡，旋转周期为 4.4 d。