Disk corona interaction: mechanism for the disk truncation and spectrum change in low luminosity AGN

Abstract

The truncation of an optically thick, geometrically thin accretion disk is investigated in the context of low luminosity AGN (LLAGN). We generalize the disk evaporation model used in the interpretative framework of black hole X-ray binaries by including the effect of a magnetic field in accretion disks surrounding supermassive black holes. The critical transition mass accretion rate for which the disk is truncated is found to be insensitive to magnetic effects, but its inclusion leads to a smaller truncation radius in comparison to a model without its consideration. That is, a thin viscous disk is truncated for LLAGN at an Eddington ratio less than 0.03 for a standard viscosity parameter ($\alpha =0.3$). An increase of the viscosity parameter results in a higher critical transition mass accretion rate and a correspondingly smaller truncation distance, the latter accentuated by greater magnetic energy densities in the disk. Based on these results, the truncation radii inferred from spectral fits of LLAGN published in the literature are consistent with the disk evaporation model. The infrared emission arising from the truncated geometrically thin accretion disks may be responsible for the red bump seen in such LLAGN.

21 pages, 2 figures. Accepted for publication in ApJ

References in corpus (10)

• Accretion disc viscosity: how big is alpha?
• Low-Luminosity Active Galactic Nuclei: Are They UV-Faint and Radio Loud?
• The Existence of Inner Cool Disks in the Low Hard State of Accreting Black Holes
• Revisiting the "Fundamental Plane" of Black Hole Activity at Extremely Low Luminosities
• Re-condensation from an ADAF into an inner disk - the intermediate state of black hole accretion?
• On the Properties of Inner Cool Disks in the Hard State of Black Hole X-Ray Transient Systems
• An inner disk below the ADAF: the intermediate spectral state of black hole accretion
• Disk-Evaporation Fed Corona: Structure and Evaporation Feature with Magnetic Field
• Kinematics of the Broad Line Region in M81
• The advection-dominated accretion flow+thin accretion disk model for two low-luminosity active galactic nuclei: M81 and NGC4579

Cited by in corpus (23)

• Hot Accretion Flows Around Black Holes
• Spectral Models for Low-luminosity Active Galactic Nuclei in LINERs: The Role of Advection-dominated Accretion and Jets
• A possible mechanism for multiple changing look phenomenon in Active Galactic Nuclei
• The Nuclear Near-Infrared Spectral Properties of Nearby Galaxies
• X-ray and Optical Correlation of Type I Seyfert NGC 3516 Studied with Suzaku and Japanese Ground-Based Telescopes
• SWIFT J1910.2-0546: A possible black hole binary with a retrograde spin or truncated disk
• The role of the accretion disk, dust, and jets in the IR emission of low-luminosity AGN
• The condensation of the corona for the correlation between the hard X-ray photon index $\Gamma$ and the reflection scaling factor $\Re$ in active galactic nuclei
• An Explanation for Overrepresentation of Tidal Disruption Events in Post-starburst Galaxies
• The disk evaporation model for the spectral features of low-luminosity active galactic nuclei
• Evidence for Disk Truncation at Low Accretion States of the Black Hole Binary MAXI J1820+070 Observed by NuSTAR and XMM-Newton
• A Cigale module tailored (not only) for Low-Luminosity AGN
• Constraints on the Viscosity and Magnetic Field in Hot Accretion Flows around Black Holes
• Detection of the high energy cut-off from the Seyfert 1.5 galaxy NGC 5273
• The Large Amplitude X-ray Variability in NGC 7589: Possible Evidence for Accretion Mode Transition
• A systematic study of the advection-dominated accretion flow for the origin of the X-ray emission in weakly magnetized low-level accreting neutron star
• The Average Soft X-ray Spectra of eROSITA Active Galactic Nuclei
• Advection-dominated accretion flow for the varied transition luminosities in black hole X-ray binaries
• A toy model for X-ray spectral variability of active galactic nuclei
• The Composite Spectral Energy Distribution of Quasars is Surprisingly Universal Since Cosmic Noon
• Low frequency QPOs and possible change in the accretion geometry during the outbursts of Aquila X$-$1
• Back to basics: Little Red Dots as galaxies and dust-obscured AGNs in a synthetic NIRCam sky simulated with L-GalaxiesBH
• Fast giant flares in discs around supermassive black holes