Multimessenger time-domain signatures of supermassive black hole binaries
Multimessenger time-domain signatures of supermassive black hole binaries
复制标题
超大质量黑洞双星的多信使时域特征
DOI：
10.1093/mnras/stab3713
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发表时间：
2021
影响因子：
4.8
通讯作者：
Trump, Jonathan R.
中科院分区：
文献类型：
--
作者：
Charisi, Maria;Taylor, Stephen R.;Runnoe, Jessie;Bogdanovic, Tamara;Trump, Jonathan R.
超大质量黑洞双星(SMBHBs)是星系合并的自然产物，应该经常在星系核中形成。亚帕秒双星可以从其明亮的电磁发射中识别出来，例如具有多普勒频移宽发射线的活动星系核(AGN)或具有周期变化的AGN，以及从强引力辐射的发射中识别。最大质量的双星(总质量&108M⊙)在纳赫兹波段发射，是脉冲星定时阵列(PTA)的目标。在这里，我们研究了SMBHBs的电磁波和引力波特征之间的协同作用。我们将这两个信号与双星的轨道动力学联系起来，并检查它们之间的共同联系，为联合多星观测奠定了基础。我们发现，由相对论多普勒增强引起的周期变化是与GWS相关联的最有希望的电磁特征。我们描述了联合观测可行的参数空间(双星总质量/啁啾质量与双星周期/GW频率)。目前，受PTA灵敏度的限制，多传送器探测只能对最大质量和最邻近的星系进行。然而，我们证明，随着PTA在未来几年收集更多的数据，重叠的参数空间预计将显著扩大。
Supermassive black hole binaries (SMBHBs) are a natural outcome of galaxy mergers and should form frequently in galactic nuclei. Sub-parsec binaries can be identified from their bright electromagnetic emission, e.g. Active Galactic Nuclei (AGNs) with Doppler shifted broad emission lines or AGN with periodic variability, as well as from the emission of strong gravitational radiation. The most massive binaries (with total mass >108M⊙) emit in the nanohertz band and are targeted by Pulsar Timing Arrays (PTAs). Here we examine the synergy between electromagnetic and gravitational wave signatures of SMBHBs. We connect both signals to the orbital dynamics of the binary and examine the common link between them, laying the foundation for joint multimessenger observations. We find that periodic variability arising from relativistic Doppler boost is the most promising electromagnetic signature to connect with GWs. We delineate the parameter space (binary total mass/chirp mass versus binary period/GW frequency) for which joint observations are feasible. Currently multimessenger detections are possible only for the most massive and nearby galaxies, limited by the sensitivity of PTAs. However, we demonstrate that as PTAs collect more data in the upcoming years, the overlapping parameter space is expected to expand significantly.