Revisiting UV/optical continuum time lags in AGN
arXiv:2309.05392 · doi:10.1093/mnras/stad2701
Abstract
In this paper, we present an updated version of our model (KYNXiltr) which considers thermal reverberation of a standard Novikov-Thorne accretion disc illuminated by an X-ray point-like source. Previously, the model considered only two cases of black hole spins, and assumed a colour correction factor . Now, we extend the model to any spin value and colour correction. In addition, we consider two scenarios of powering the X-ray corona, either via accretion, or external to the accretion disc. We use KYNXiltr to fit the observed time lags obtained from intense monitoring of four local Seyfert galaxies (NGC 5548, NGC 4395, Mrk 817, and Fairall 9). We consider various combinations of black hole spin, colour correction, corona height, and fraction of accretion power transferred to the corona. The model fits well the overall time-lags spectrum in these sources (for a large parameter space). For NGC 4593 only, we detect a significant excess of delays in the U-band. The contribution of the diffuse BLR emission in the time-lags spectrum of this source is significant. It is possible to reduce the large best-fitting parameter space by combining the results with additional information, such as the observed Eddington ratio and average X-ray luminosity. We also provide an update to the analytic expression provided by Kammoun et al., for an X-ray source that is not powered by the accretion process, which can be used for any value of colour correction, and for two values of the black hole spin (0 and 0.998).
arXiv commentAccepted for publication in MNRAS
References in corpus (32)
- SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
- Array Programming with NumPy
- Global Optimization by Basin-Hopping and the Lowest Energy Structures of Lennard-Jones Clusters Containing up to 110 Atoms
- Methods and results of an automatic analysis of a complete sample of Swift-XRT observations of GRBs
- HI4PI: A full-sky HI survey based on EBHIS and GASS
- Intrinsic disc emission and the Soft X-ray Excess in AGN
- X-ray reflected spectra from accretion disk models. III. A complete grid of ionized reflection calculations
- Piecing Together the X-ray Background: Bolometric Corrections for Active Galactic Nuclei
- The AGN Black Hole Mass Database
- Space Telescope and Optical Reverberation Mapping Project. III. Optical Continuum Emission and Broad-Band Time Delays in NGC 5548
- Space Telescope and Optical Reverberation Mapping Project. II. Swift and HST Reverberation Mapping of the Accretion Disk of NGC 5548
- Testing thermal reprocessing in AGN accretion discs
- The First Swift Intensive AGN Accretion Disk Reverberation Mapping Survey
- High-Density Effects in X-ray Reflection Models from Accretion Disks
- Accretion disk reverberation with Hubble Space Telescope observations of NGC 4593: evidence for diffuse continuum lags
- X-ray/UV/optical variability of NGC 4593 with Swift: Reprocessing of X-rays by an extended reprocessor
- Intensive disc-reverberation mapping of Fairall 9: 1st year of Swift & LCO monitoring
- Supermassive black holes with high accretion rates in active galactic nuclei. XI. Accretion disk reverberation mapping of Mrk 142
- Modeling the UV/optical continuum time-lags in AGN
- Spectral Hardening in Black Hole Accretion: Giving Spectral Modelers an f
- Space Telescope and Optical Reverberation Mapping Project. IX. Velocity-Delay Maps for Broad Emission Lines in NGC 5548
- UV/optical disk thermal reverberation in AGN: an in-depth study with an analytic prescription for the time-lag spectra
- On the multi-wavelength variability of Mrk 110: Two components acting at different timescales
- Evidence for variability timescale dependent UV/X-ray delay in Seyfert 1 AGN NGC 7469
- A hard look at thermal reverberation and optical/UV lags in NGC 5548
- UV/Optical disk reverberation lags despite a faint X-ray corona in the AGN Mrk 335
- A physical model for the broadband energy spectrum of X-ray illuminated accretion discs: fitting the spectral energy distribution of NGC 5548
- A physical model for the UV/optical power spectra of AGN
- The luminosity-dependent contribution from the broad line region to the wavelength-dependent lags in Mrk 110
- Optical continuum photometric reverberation mapping of the Seyfert-1 galaxy Mrk509
- Multiwavelength power-spectrum analysis of NGC 5548
- Estimating reddening of the continuum and broad-line region of active galactic nuclei: the mean reddening of NGC 5548 and the size of the accretion disc
Cited by in corpus (9)
- Broadband X-ray/UV/optical time-resolved spectroscopy of NGC 5548: The origin of the UV/optical variability in active galactic nuclei
- Continuum optical-UV and X-ray variability of AGN: current results and future challenges
- Spectral variability studies in Active Galactic Nuclei: Exploring continuum and emission line regions in the age of LSST and JWST
- X-ray reverberation modelling of the continuum, optical/UV time-lags in quasars
- Application of the FRADO model of BLR formation to the Seyfert galaxy NGC 5548 and the first step toward determining the Hubble constant
- Accretion disc reverberation mapping in a high-redshift quasar
- HALO I: Photometric continuum reverberation mapping of Fairall 9
- The UV/optical Continuum Reverberation Mapping of Eight Active Galactic Nuclei with Swift: Further Evidence for the Outer Component
- The X-ray/UV Connection in NGC 5548: A Rapidly Varying Corona