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arXiv · 2307.00722

Implications for the Supermassive Black Hole Binaries from the NANOGrav 15-year Data Set

Yan-Chen Bi·Yu-Mei Wu·Zu-Cheng Chen·Qing-Guo Huang
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Abstract

NANOGrav, EPTA, PPTA, and CPTA have announced the evidence for a stochastic signal from their latest data sets. Supermassive black hole binaries (SMBHBs) are supposed to be the most promising gravitational-wave (GW) sources of pulsar timing arrays. Assuming an astro-informed formation model, we use the NANOGrav 15-year data set to constrain the gravitational wave background (GWB) from SMBHBs. Our results prefer a large turn-over eccentricity of the SMBHB orbit when GWs begin to dominate the SMBHBs evolution. Furthermore, the GWB spectrum is extrapolated to the space-borne GW detector frequency band by including inspiral-merge-cutoff phases of SMBHBs and should be detected by LISA, Taiji and TianQin in the near future.

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Yan-Chen Bi, Yu-Mei Wu, Zu-Cheng Chen, Qing-Guo Huang. 2023-07-03. Implications for the Supermassive Black Hole Binaries from the NANOGrav 15-year Data Set. https://doi.org/10.1007/s11433-023-2252-4

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