arXiv:2307.00722·v2·Cosmology and Nongalactic Astrophysics
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🇨🇳
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.
Comments: 8 pages, 3 figures, 3 tables; version accepted for publication in SCPMA