As a powerful source of gravitational waves (GW), a supermassive black hole (SMBH) merger may be accompanied by a relativistic jet that leads to detectable electromagnetic (EM) emission. We model the propagation of post-merger jets inside a pre-merger wind bubble formed by disk winds, and calculate multiwavelength EM spectra from the forward shock region. We show that the nonthermal EM signals from SMBH mergers are detectable up to the detection horizon of future GW facilities such as the Laser Interferometer Space Antenna (LISA). Calculations based on our model predict slowly fading transients with time delays from days to months after the coalescence, leading to implications for EM follow-up observations after the GW detection.

作为引力波 (GW) 的强大来源，超大质量黑洞 (SMBH) 合并可能伴随着导致可探测电磁 (EM) 发射的相对论性喷流。我们对合并后喷流在盘风形成的合并前风泡内的传播进行建模，并计算前激波区域的多波长电磁波谱。我们表明，来自 SMBH 合并的非热电磁信号在未来 GW 设施（如激光干涉仪空间天线（LISA））的检测范围内是可检测到的。基于我们的模型的计算预测缓慢衰落的瞬态，并在合并后数天到数月的时间延迟，从而对 GW 检测后的 EM 后续观察产生影响。