Active Galactic Nuclei as scaled-up Galactic black holes

Abstract

A long-standing question is whether active galactic nuclei (AGN) vary like Galactic black hole systems when appropriately scaled up by mass (refs 1-3). If so, we can then determine how AGN should behave on cosmological timescales by studying the brighter and much faster varying Galactic systems. As X-ray emission is produced very close to the black holes, it provides one of the best diagnostics of their behaviour. A characteristic timescale, which potentially could tell us about the mass of the black hole, is found in the X-ray variations from both AGN and Galactic black holes (refs 1-6), but whether it is physically meaningful to compare the two has been questioned (ref 7). Here we report that, after correcting for variations in the accretion rate, the timescales can be physically linked, revealing that the accretion process is exactly the same for small and large black holes. Strong support for this linkage comes, perhaps surprisingly, from the permitted optical emission lines in AGN whose widths (in both broad-line AGN and narrow-emission-line Seyfert 1 galaxies) correlate strongly with the characteristic X-ray timescale, exactly as expected from the AGN black hole masses and accretion rates. So AGN really are just scaled-up Galactic black holes.

10 pages of main paper, 3 figures and 16 pages of Supplementary Information, all in one PDF file

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• The Radius-Luminosity Relationship for Active Galactic Nuclei: The Effect of Host-Galaxy Starlight on Luminosity Measurements
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• Using Leaked Power to Measure Intrinsic AGN Power Spectra of Red-Noise Time Series
• Exploratory X-ray Monitoring of Luminous Radio-Quiet Quasars at High Redshift: No Evidence for Evolution in X-ray Variability
• The efficient low-mass Seyfert MCG-05-23-016
• The lively accretion disk in NGC 2992. II. The 2019/2021 X-ray monitoring campaigns
• Discovery of soft and hard X-ray time lags in low-mass AGNs
• The Accretion Disc-Jet Connection in Blazars
• Q2122-444: a naked AGN fully dressed
• Searching for Quasi-periodic Oscillations in Active Galactic Nuclei of the Chandra Deep Field South
• Constraining X-ray reflection in the low-luminosity AGN NGC 3718 using NuSTAR and XMM--Newton
• The nature of the broadband X-ray variability in the dwarf Seyfert galaxy NGC 4395
• X-ray reverberation lags from the 1.5 Seyfert galaxy NGC 5273
• Extensive X-ray variability studies of NGC 7314 using long XMM-Newton observations
• OPTICAM: A triple-camera optical system designed to explore the fastest timescales in Astronomy
• Fundamental Reference AGN Monitoring Experiment (FRAMEx) III: Radio Emission in the Immediate Vicinity of Radio Quiet AGNs
• Changing Accretion Geometry of Seyfert 1 Mrk 335 with {\it NuSTAR}: A Comparative Study
• Characterizing black hole variability with nonlinear methods: the case of the X-ray Nova 4U 1543-47
• X-ray time lags in PG 1211+143
• GALEX Measurements of the Big Blue Bump in Soft X-ray Selected AGN
• Assessing indirect methods to determine black hole masses using NGC 4151
• Populations of highly variable X-ray sources in the XMM$-$Newton slew survey
• Optical variability modeling of newly identified blazar candidates behind Magellanic Clouds
• Accretion and jets in a low luminosity AGN: the nucleus of NGC 1052
• Fast Timing Analysis of Cygnus X-1 using SPI on board INTEGRAL
• RMS-Flux Relation and Disc-Jet Connection in Blazars in the Context of the Internal Shocks Model
• The X-ray variability of AGN: power-spectrum and variance analysis of the Swift/BAT light curves
• Highly polarised microstructure from the repeating FRB 20180916B
• The Suzaku broadband X-ray spectrum of the dwarf Seyfert galaxy NGC4395
• Estimating black hole masses in obscured AGN using X-rays
• Measuring the black hole mass in Ultraluminous X-ray Sources with the X-ray Scaling Method
• Are quasars reliable standard candles?
• The non-linear X-ray/UV relation in active galactic nuclei: contribution of instrumental effects on the X-ray variability
• Complex Variability of Kepler AGN Revealed by Recurrence Analysis
• Exploring the Link between the X-ray Power Spectra and Energy Spectra of Active Galactic Nuclei
• Flux and spectral variability of Mrk 421 during its moderate activity state using NuSTAR: Possible accretion disc contribution?
• Modelling variability power spectra of active galaxies from irregular time series
• Is the anti-correlation between the X-ray variability amplitude and black hole mass of AGNs intrinsic?
• A jet-dominated model for a broad-band spectral energy distribution of the nearby low-luminosity active galactic nucleus in M94
• A Sample Bias in Quasar Variability Studies
• Fourier time lags in the dwarf nova SS Cygni
• Study of accretion flows around an ultraluminous X-ray source M82 X-1 using NuSTAR data
• Review the possible advective disk structures around a black hole with two-type gas inflows
• The XMM deep survey in the CDF-S. X. X-ray variability of bright sources
• Deconvolving X-ray Spectral Variability Components in the Seyfert 1.5 NGC 3227
• AGNet: Weighing Black Holes with Deep Learning
• Long-term hard X-ray variability properties of Swift-BAT blazars
• Long-term AGN variability and the case of GSN 069
• Investigating Non-linear and Stochastic Hard X-ray Variability of Active Galactic Nuclei using Recurrence Analysis
• Probing black-hole accretion through time variability
• XMM-Newton --NuSTAR monitoring campaign of the Seyfert 1 galaxy IC 4329A
• An Intermediate-Mass Black Hole Candidate in M51?
• X-ray Eclipses of Active Galactic Nuclei
• X-ray spectral and temporal analysis of Narrow Line Seyfert 1 galaxy Was 61
• Multi-wavelength properties of changing-state active galactic nuclei: I. the evolution of soft excess and X-ray continuum
• Constraining Energy-dependent emissivity profiles of AGN inflows
• Compact and variable radio emission from an active galaxy with supersoft X-ray emission
• Dynamical Measurement of Supermassive Black Hole Masses: QPE Timing Method
• Characterising continuum variability in the radio-loud narrow-line Seyfert 1 galaxy IRAS 17020+4544
• X-ray polarimetry-timing
• Characterisation of the X-ray point source variability in the eROSITA south ecliptic pole field
• Reverberation lags viewed in hard X-rays from an accreting stellar-mass black hole
• High frequency breaks in optical active galactic nuclei power spectral density
• X-ray view of four high-luminosity Swift/BAT AGN: Unveiling obscuration and reflection with Suzaku
• A Systematic Study of the Short-Term X-ray Variability of Seyfert Galaxies I. Diversity of the X-ray Rms Spectra
• A compact symmetric ejection from the low mass AGN in the LINER galaxy NGC 4293
• Infrared interferometry to spatially and spectrally resolve jets in X-ray binaries
• Selected Chapters on Active Galactic Nuclei as Relativistic Systems
• A relativistic orbit model for temporal properties of AGN
• The NuSTAR view of the Seyfert Galaxy HE 0436-4717
• Photometric Selection of type 1 Quasars in the XMM-LSS Field with Machine Learning and the Disk-Corona Connection
• A Minimal Time Scale for the Spectral States of GX 339-4
• An Analytical Fourier-Transformation Model for the Production of Hard and Soft X-Ray Time Lags in AGNs: Application to 1H 0707-495
• A ~1-hour X-ray periodicity in an active galaxy RE J1034+396
• Not so Swift: 20 years of multiwavelength observations of Mrk 421 and Mrk 501
• The eROSITA DR1 variability catalogue
• Long-term Evolution of the Short-term X-ray Variability of the Jetted TDE Swift J1644+57
• Outer disc edge: properties of low frequency aperiodic variability in ultracompact interacting binaries
• Automated algorithms to build Active Galactic Nuclei classifiers
• AGN cool feedback and analogy with X-ray binaries: from radiation pressure to cosmic ray driven outflows
• Magnetic Reconnection as a Potential Driver of X-ray Variability in Active Galactic Nuclei
• Exploratory X-Ray Monitoring of Luminous Radio-Quiet Quasars at High Redshift: Extended Time-Series Analyses and Stacked Imaging Spectroscopy
• More evidence for extinction of activity in galaxies
• A 2.5-dimensional viscous, resistive, advective magnetized accretion-outflow coupling in black hole systems: A higher order polynomial approximation. I
• Searching for supermassive black holes binaries within SRG/eROSITA-De I: Properties of the X-ray selected candidates
• Photometric variability in star-forming galaxies as evidence for low-mass AGN and a precursor to quenching
• STROBE-X: A probe-class mission for X-ray spectroscopy and timing on timescales from microseconds to years
• The ensemble broad-frequency power spectrum of Stripe-82 quasars from multiple surveys
• Study of Intra-Day Flux Distributions of Blazars Using XMM-Newton Satellite
• Optical variability of eight FRII-type quasars with 13-yr photometric light curves
• Disk-corona modeling for spectral index and luminosity correlation of tidal disruption events
• A Decade of Near-Infrared Variability in NGC4388: Insights into the AGN Structure
• Untangling the Complex Nature of AGN Variability with Fairall 9
• The nature of the variable millimetre-selected AGN in the Brightest Cluster Galaxy of Abell 851
• Overmassive and Undermassive Massive Black Holes: The Role of Environment and Gravitational-Wave Recoils
• Accretion Geometry of Black Hole X-ray Binaries: Insights from X-ray Observations
• Strong X-ray Variability of I Zwicky 1: Obscuration from Clumpy Accretion-Disk Winds
• Intensive X-ray/UVOIR continuum reverberation mapping of the Seyfert AGN MCG+08-11-11
• Black Hole Jet Unification in the Fermi Era
• Energy dependence of the X-ray power spectrum in NGC4051 and NGC4395
• Time Domain Astronomy with the THESEUS Satellite
• Probing extreme black-hole outflows on short timescales via high spectral-resolution X-ray imagers
• Black hole masses from X-rays
• The extreme properties of the nearby hyper-Eddington accreting Active Galactic Nucleus in IRAS 04416+1215
• Emission line profiles and X-ray observations of Broad and Narrow Line Seyfert 1 Galaxies
• Fourier spectral-timing techniques for the study of accreting black holes
• "Spoon-feeding" an AGN
• Measuring monster MBHs: maybe mighty, maybe merely massive