Future microhertz detections combined with nanohertz pulsar terms can serve as gravity echoes to measure supermassive black hole binary inspiral rates from hundreds to thousands of years in the past.
The Population of Viscosity- and Gravitational Wave-Driven Supermassive Black Hole Binaries Among Luminous AGN
4 Pith papers cite this work. Polarity classification is still indexing.
4
Pith papers citing it
abstract
Supermassive black hole binaries (SMBHBs) in galactic nuclei are thought to be a common by-product of major galaxy mergers. We use simple disk models for the circumbinary gas and for the binary-disk interaction to follow the orbital decay of SMBHBs with a range of total masses (M) and mass ratios (q), through physically distinct regions of the disk, until gravitational waves (GWs) take over their evolution. Prior to the GW-driven phase, the viscous decay is in the stalled "secondary-dominated" regime. SMBHBs spend a non-negligible fraction of 10^7 years at orbital periods t_var between a day and a year. A dedicated optical or X-ray survey could identify coalescing SMBHBs statistically, as a population of periodically variable quasars, whose abundance N_var is proportional to t_var^alpha, in a range of periods t_var around tens of weeks. SMBHBs with M < 10^7 M_sun, with 0.5 < alpha < 1.5, would probe the physics of viscous orbital decay, whereas the detection of a population of higher-mass binaries, with alpha=8/3, would confirm that their decay is driven by GWs. The lowest mass SMBHBs (M < 10^{5-6} M_sun) enter the GW-driven regime at short orbital periods, in the frequency band of the Laser Interferometric Space Antenna (LISA). While viscous processes are strongly sub-dominant in the last few years of coalescence, they could reduce the amplitude of any unresolved background of near-stationary LISA sources. We discuss constraints on the SMBHB population available from existing data, and the sensitivity and sky coverage requirements for a detection in future surveys. SMBHBs may also be identified from velocity shifts in their spectra; we discuss the expected abundance of SMBHBs as a function of their orbital velocity.
citation-role summary
background 2
citation-polarity summary
verdicts
UNVERDICTED 4roles
background 2polarities
background 2representative citing papers
3D simulations recover the critical obliquity for disc breaking predicted by semi-analytic models and reveal additional stabilization by spiral arms that can prevent breaking.
Simulations forecast 21-51% probability of resolving individual SMBH binaries with PTAs in 0-10 years, with localization areas containing ~190k early-type galaxies on average and a ranking method that excludes roughly half the candidates when galaxy properties are available.
Modeling accretion disk interactions with EMRIs allows reliable environment identification and boosts dark-siren Hubble constant precision by as much as 20% for individual events.
citing papers explorer
-
Gravity Echoes from Supermassive Black Hole Binaries
Future microhertz detections combined with nanohertz pulsar terms can serve as gravity echoes to measure supermassive black hole binary inspiral rates from hundreds to thousands of years in the past.
-
The Bardeen-Petterson effect in accreting supermassive black-hole binaries: disc breaking and critical obliquity
3D simulations recover the critical obliquity for disc breaking predicted by semi-analytic models and reveal additional stabilization by spiral arms that can prevent breaking.
-
Prospects of resolving and localising individual supermassive black hole binaries with pulsar timing arrays: the host ranking challenge
Simulations forecast 21-51% probability of resolving individual SMBH binaries with PTAs in 0-10 years, with localization areas containing ~190k early-type galaxies on average and a ranking method that excludes roughly half the candidates when galaxy properties are available.
-
Probing Active Galactic Nuclei and Measuring the Hubble constant with Extreme-Mass-Ratio Inspirals
Modeling accretion disk interactions with EMRIs allows reliable environment identification and boosts dark-siren Hubble constant precision by as much as 20% for individual events.