Self-consistently heated and cooled thin circumbinary disks still drive massive black hole binaries into long-lived non-accreting phases, producing X-ray-weak, optically variable sources that LSST and Roman could find.
Low-Frequency Gravitational Waves from Massive Black Hole Binaries: Predictions for LISA and Pulsar Timing Arrays
7 Pith papers cite this work. Polarity classification is still indexing.
abstract
The coalescence of massive black hole (BH) binaries due to galaxy mergers provides a primary source of low-frequency gravitational radiation detectable by pulsar timing measurements and by the proposed LISA (Laser Interferometry Space Antenna) observatory. We compute the expected gravitational radiation signal from sources at all redshifts by combining the predicted merger rate of galactic halos with recent measurements of the relation between BH mass, M_bh, and the velocity dispersion of its host galaxy, sigma. Our main findings are as follows: (i) the nHz frequency background is dominated by BH binaries at redshifts z<2, and existing limits from pulsar timing data place tight constraints on the allowed normalization and power-law slope of the M_bh-sigma relation or on the fraction of BH binaries that proceed to coalescence; (ii) more than half of all discrete mHz massive BH sources detectable by LISA are likely to originate at redshifts z>7; (iii) the number of LISA sources per unit redshift per year should drop substantially after reionization as long as BH formation is triggered by gas cooling in galaxies. Studies of the highest redshift sources among the few hundred detectable events per year, will provide unique information about the physics and history of black hole growth in galaxies.
citation-role summary
citation-polarity summary
years
2026 7roles
background 1polarities
background 1representative citing papers
A hierarchical Bayesian inference framework combining free-spectrum reconstruction with population-level likelihoods distinguishes finite SMBHB populations from Gaussian primordial GWB using mock PTA data.
FABLE simulation predictions for the nanohertz gravitational wave background are statistically consistent with NANOGrav 15-year data at 1–2.5σ tension, with physically motivated population modifications further improving agreement.
The gravitational wave background from supermassive black hole binaries has a universal heavy-tailed amplitude distribution with power-law index -4, causing divergent higher moments and dominance of the strongest signals by few loud sources.
The Hubble parameter produces a frequency-independent angular enhancement in LISA timing residuals above 100 mHz, potentially enabling a percent-level H0 measurement without standard sirens.
Including radiative losses in analytic models of high-redshift radio galaxies reduces predicted radio and X-ray luminosities compared to models that neglect them.
In a post-inflationary magnetogenesis scenario with time-dependent gauge couplings, magnetic anisotropic stress dominates peak GW amplitude while scalar-induced terms matter on larger scales, both showing f^3 infrared scaling for blue spectra and potentially reaching PTA frequencies.
citing papers explorer
-
Dynamics and detectability of long-lived non-accretion phases for massive black hole binaries in cold, thermally regulating disks
Self-consistently heated and cooled thin circumbinary disks still drive massive black hole binaries into long-lived non-accreting phases, producing X-ray-weak, optically variable sources that LSST and Roman could find.
-
Population statistics of nanohertz gravitational wave sources
A hierarchical Bayesian inference framework combining free-spectrum reconstruction with population-level likelihoods distinguishes finite SMBHB populations from Gaussian primordial GWB using mock PTA data.
-
Comparing gravitational wave background predictions from cosmological simulations to pulsar timing observations
FABLE simulation predictions for the nanohertz gravitational wave background are statistically consistent with NANOGrav 15-year data at 1–2.5σ tension, with physically motivated population modifications further improving agreement.
-
The Heavy Tailed Non-Gaussianity of the Supermassive Black Hole Gravitational Wave Background
The gravitational wave background from supermassive black hole binaries has a universal heavy-tailed amplitude distribution with power-law index -4, causing divergent higher moments and dominance of the strongest signals by few loud sources.
-
Impact of $H_0$ on gravitational wave propagation: prospects for the LISA mission
The Hubble parameter produces a frequency-independent angular enhancement in LISA timing residuals above 100 mHz, potentially enabling a percent-level H0 measurement without standard sirens.
-
A simulation-based analytic model of radio galaxies II: self-consistent radiative losses
Including radiative losses in analytic models of high-redshift radio galaxies reduces predicted radio and X-ray luminosities compared to models that neglect them.
-
Gravitational Waves from Post-Inflationary Magnetism: Direct and Scalar-Induced Contributions
In a post-inflationary magnetogenesis scenario with time-dependent gauge couplings, magnetic anisotropic stress dominates peak GW amplitude while scalar-induced terms matter on larger scales, both showing f^3 infrared scaling for blue spectra and potentially reaching PTA frequencies.