Massive black hole binary systems and the NANOGrav 12.5 yr results
H Middleton, A Sesana, S Chen, A Vecchio, W Del Pozzo, PA Rosado
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY | OXFORD UNIV PRESS | Published : 2021
The North American Nanohertz Observatory for Gravitational Waves (NANOGrav) recently reported evidence for the presence of a common stochastic signal across their array of pulsars. The origin of this signal is still unclear. One possibility is that it is due to a stochastic gravitational-wave background (SGWB) in the ∼1-10 nHz frequency region. Taking the NANOGrav observational result at face value, we show that this signal would be fully consistent with an SGWB produced by an unresolved population of in-spiralling massive black hole binaries (MBHBs) predicted by current theoretical models. Considering an astrophysically agnostic model, the MBHB merger rate is loosely constrained. Including ..View full abstract
Awarded by Australian Research Council Centre of Excellence for Gravitational Wave Discovery (OzGrav)
Awarded by European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program ERC-2018-COG
Parts of work were performed on the OzSTAR national facility at Swinburne University of Technology. The OzSTAR program receives funding in part from the Astronomy National Collaborative Research Infrastructure Strategy (NSCRIS) allocation provided by the Australian Government. HM is supported by the Australian Research Council Centre of Excellence for Gravitational Wave Discovery (OzGrav) (project no. CE170100004). AS is supported by the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program ERC-2018-COG under grant agreement no. 818691 (B Massive). SC acknowledges support from the CNRS, CEA, CNES in France. AV acknowledges support from the Royal Society and the Wolfson Foundation. The authors acknowledge support from the European Pulsar Timing Array (EPTA), the North American Nanohertz Observatory for Gravitational Waves (NANOGrav), the Parkes Pulsar Timng Array (PPTA), and the International Pulsar Timing Array (IPTA).