Spiral Arms in Broad-line Regions of Active Galactic Nuclei. II. Loosely Wound Cases: Reverberation Properties

Abstract

There has recently been growing evidence that broad-line regions (BLRs) in active galactic nuclei have regular substructures, such as spiral arms, which are supported by the fact that the radii of BLRs measured by RM observations are generally consistent with the self-gravitating regions of accretion disks. We have shown in Paper I that the spiral arms excited by the gravitational instabilities in these regions may exist in some disk-like BLRs. As the second paper of the series, we investigate the loosely wound spiral arms excited by gravitational instabilities in disk-like BLRs and present their observational characteristics. Following the treatments of Adams et al. (1989), we solve the governing integro-differential equation by a matrix scheme. The emission-line profiles, velocity-delay maps, and velocity-resolved lags of the BLR spiral arms are calculated. We find that the spiral arms can explain some phenomena in observations: (1) the emission-line profiles in the mean and rms spectra have different asymmetries, (2) some velocity-delay maps, e.g., NGC 5548, have complex sub-features (incomplete ellipse), (3) the timescales of the asymmetry changes in emission-line profiles (rms spectra) are short. These features are attractive for modeling the observed line profiles and the properties of reverberation, and for revealing the details of the BLR geometry and kinematics.

24 pages, 14 figures, accepted for publication in Astronomy & Astrophysics

References in corpus (27)

• Spiral Density Waves in a Young Protoplanetary Disk
• Supermassive Black Holes with High Accretion Rates in Active Galactic Nuclei. IV. H$\beta$ Time Lags and Implications for Super-Eddington Accretion
• The Radius-Luminosity Relationship Depends on Optical Spectra in Active Galactic Nuclei
• The Disk Substructures at High Angular Resolution Project (DSHARP): III. Spiral Structures in the Millimeter Continuum of the Elias 27, IM Lup, and WaOph 6 Disks
• Space Telescope and Optical Reverberation Mapping Project. V. Optical Spectroscopic Campaign and Emission-Line Analysis for NGC 5548
• Double-peaked profiles: ubiquitous signatures of disks in the Broad Emission Lines of Active Galactic Nuclei
• The First Spectroscopically Resolved Sub-parsec Orbit of a Supermassive Binary Black Hole
• First Results from the Lick AGN Monitoring Project: The Mass of the Black Hole in Arp 151
• Failed radiatively Accelerated Dusty Outflow model of the Broad Line Region in Active Galactic Nuclei. I. Analytical solution
• Reverberation Measurements of the Inner Radii of the Dust Tori in Quasars
• Monitoring AGNs with H$\beta$ Asymmetry. III. Long-term Reverberation Mapping Results of 15 Palomar-Green Quasars
• Reverberation Mapping Measurements of Black Hole Masses and Broad-Line Region Kinematics in Mrk 817 and NGC 7469
• OzDES Reverberation Mapping Program: The first Mg II lags from five years of monitoring
• Reverberation Mapping of Changing-look Active Galactic Nucleus NGC 3516
• The Lick AGN Monitoring Project 2016: Dynamical Modeling of Velocity-Resolved H\b{eta} Lags in Luminous Seyfert Galaxies
• Evidence for Two Distinct Broad-Line Regions from Reverberation Mapping of PG 0026+129
• Rimmed and Rippled Accretion Disc Models to Explain AGN Continuum Lags
• Monitoring AGNs with Hβ Asymmetry. II. Reverberation Mapping of Three Seyfert Galaxies Historically Displaying Hβ Profiles with Changing Asymmetry: Mrk 79, NGC 3227, and Mrk 841
• Broad-line Region of the Quasar PG 2130+099 from a Two-Year Reverberation Mapping Campaign with High Cadence
• Active Galactic Nuclei with Ultra-fast Outflows Monitoring Project: The Broad-line Region of Mrk 79 as a Disk Wind
• Short timescale variations of the Hα double-peaked profile of the nucleus of NGC 1097
• The Seoul National University AGN monitoring project. II. BLR size and black hole mass of two AGNs
• Variation of Broad Emission Lines from QSOs with Optical/UV Periodicity to Test the Interpretation of Supermassive Binary Black Holes
• Spiral Arms in Broad-line Regions of Active Galactic Nuclei. I. Reverberation and Differential Interferometric Signals of Tightly Wound Cases
• Global Spiral Density Wave Modes in Protoplanetary Disks: Morphology of Spiral Arms
• Spectral variability of the 3C 390.3 nucleus for more than 20 years -- II. Variability of the broad emission-line profiles and He II $\lambda 4686$A emission-line fluxes
• Generation of potential/surface density pairs in flat disks Power law distributions

Cited by in corpus (4)

• The transient event in NGC 1566 from 2017 to 2019 -- I. An eccentric accretion disk and a turbulent, disk-dominated broad-line region unveiled by double-peaked Ca II and O I lines
• Velocity-Resolved Ionization Mapping of Broad Line Region. I. Insights into Diverse Geometry and Kinematics
• Search for Quasar Pairs with $Gaia$ Astrometric Data. I. Method and Candidates
• X-ray Quasi-Periodic Oscillations in Active Galactic Nuclei and Their Implications for the Changing Look Phenomenon