LIGO/Virgo S190814bv is the first high-probability neutron star - black hole (NSBH) merger candidate, whose gravitational waves (GWs) triggered LIGO/Virgo detectors at 21:10:39.012957 UT, 14 August 2019. It has a probability $>99\%$ of being an NSBH merger, with a low false alarm rate (FAR) of 1 per 1.559e+25 years. For an NSBH merger, electromagnetic counterparts (especially short gamma-ray bursts (GRBs)) are generally expected. However, no electromagnetic counterpart has been found in the extensive follow-up observing campaign. In the present work, we propose a novel explanation to this null result. In our scenario, LIGO/Virgo S190814bv is just a GW mirror image of the real NSBH merger which should be detected before 14 September 2015, but at that time we had no ability to detect its GW signals. The electromagnetic counterparts associated with the real NSBH merger should be found in the archive data before 14 September 2015. In this work, we indeed find 9 short GRBs as the possible electromagnetic counterparts.

中文翻译：

---

第一次高概率 NSBH 合并 LIGO/Virgo S190814bv 的可能电磁对应物

LIGO/Virgo S190814bv 是第一个高概率中子星 - 黑洞 (NSBH) 合并候选者，其引力波 (GWs) 在 2019 年 8 月 14 日 21:10:39.012957 UT 触发了 LIGO/Virgo 探测器。它有一个概率 $> 99\%$ 是 NSBH 合并，每 1.559e+25 年误报率 (FAR) 低，为 1。对于 NSBH 合并，通常会出现电磁对应物（尤其是短伽马射线暴 (GRB)）。然而，在广泛的后续观测活动中没有发现电磁对应物。在目前的工作中，我们对这个无效结果提出了一种新的解释。在我们的场景中，LIGO/Virgo S190814bv 只是真实 NSBH 合并的 GW 镜像，应该在 2015 年 9 月 14 日之前检测到，但当时我们无法检测到它的 GW 信号。