Spectral variability of the 3C 390.3 nucleus for more than twenty years. I. Variability of the broad and narrow emission-line fluxes

Abstract

We summarize results of the analysis of the optical variability of the continuum and emission-line fluxes in the 3C390.3 nucleus during 1992-2014. The [OIII]5007 flux increases monotonically by $\approx$30 per cent in 2003-2014. The narrow Balmer lines show similar monotonic increase, while the variability patterns of the [OI]6300 narrow line are completely different from that of [OIII]. The reverberation lags are found to be 88.6$\pm$8.4, 161$\pm$15, and 113$\pm$14d for the H$\beta$, H$\alpha$, and H$\gamma$ broad emission-lines, respectively. The reverberation mass of the central black hole equals to (1.87$\pm$0.26)$\times 10^9{M}_{\odot }$ and (2.81$\pm$0.38)$\times 10^9{M}_{\odot }$, for the H$\beta$ and H$\alpha$ lines and assuming a scaling factor that converts the virial product to a mass to be f=5.5. A difference between both masses can point to a difference between kinematics of the H$\alpha$ and H$\beta$ emission regions. We show that the reverberation mapping can only be applied to the entire period of observations of the 3C390.3 nucleus after removing a long-term trend. This trend has been expressed by a slowly varying scalefactor c(t) in the power-law relationship between the line and continuum fluxes: $F_{line}\propto c(t)F_{cont}^a$. We find the power-law index $a$ equals to 0.77 and 0.54 for the H$\beta$ and H$\alpha$ lines, respectively. The observed relationship between the Balmer decrement and the optical continuum flux is as follows: $F(H\alpha )/F(H\beta )\propto F_{cont}^{-0.20}$ and $F(H\beta )/F(H\gamma )\propto F_{cont}^{-0.18}$. The 3C390.3 nucleus is an "outsider" in the relationship between optical luminosity and black hole mass. Its Eddington ratio is $E_{bol}/E_{Edd}$ = 0.0037.

References in corpus (28)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• Reverberation Measurements for 17 Quasars and the Size-Mass-Luminosity Relations in Active Galactic Nuclei
• Central Masses and Broad-Line Region Sizes of Active Galactic Nuclei. II. A Homogeneous Analysis of a Large Reverberation-Mapping Database
• Central Masses and Broad-Line Region Sizes of Active Galactic Nuclei: I. Comparing the Photoionization and Reverberation Techniques
• Supermassive Black Holes in Active Galactic Nuclei. II. Calibration of the M-sigma Relationship for AGNs
• On Uncertainties in Cross-Correlation Lags and the Reality of Wavelength-Dependent Continuum Lags in Active Galactic Nuclei
• Systematic Effects in Measurement of Black Hole Masses by Emission-Line Reverberation of Active Galactic Nuclei: Eddington Ratio and Inclination
• The Lick AGN Monitoring Project: Broad-Line Region Radii and Black Hole Masses from Reverberation Mapping of Hbeta
• An expanded M_bh-sigma diagram, and a new calibration of active galactic nuclei masses
• Reverberation Mapping Measurements of Black Hole Masses in Six Local Seyfert Galaxies
• Optical Continuum and Emission-Line Variability of Seyfert 1 Galaxies
• Stellar Velocity Dispersion Measurements in High-Luminosity Quasar Hosts and Implications for the AGN Black Hole Mass Scale
• Reverberation Mapping Results for Five Seyfert 1 Galaxies
• The Lick AGN Monitoring Project: Reverberation Mapping of Optical Hydrogen and Helium Recombination Lines
• Diverse Broad Line Region Kinematic Signatures From Reverberation Mapping
• The Size of the Narrow-Line Emitting Region in the Seyfert 1 Galaxy NGC 5548 from Emission-Line Variability
• Steps toward Determination of the Size and Structure of the Broad-Line Region in Active Galactic Nuclei. XII. Ground-Based Monitoring of 3C 390.3
• Long-Term Profile Variability of Double Peaked Emission Lines in Active Galactic Nuclei
• Black Hole Masses of Active Galaxies with Double-Peaked Balmer Emission Lines
• Intermediate resolution H-beta spectroscopy and photometric monitoring of 3C 390.3 I. Further evidence of a nuclear accretion disk
• Optical Monitoring of the Broad-Line Radio Galaxy 3C390.3
• Spectral optical monitoring of 3C390.3 in 1995-2007: I. Light curves and flux variation of the continuum and broad lines
• BLR kinematics and Black Hole Mass in Markarian 6
• Interpreting the Variability of Double-Peaked Emission Lines in Active Galactic Nuclei with Stochastically Perturbed Accretion Disk Models
• A Study of Time Variations of UV Continuum and Emission Lines in 3C390.3
• The Nature of the Broad--Line--Region in the Radio--Loud AGN 3C390.3
• Time Series Analysis of Active Galactic Nuclei: The case of Arp 102B, 3C 390.3, NGC 5548 and NGC 4051
• Spectropolarimetric monitoring of active galaxy 3C390.3 with 6m telescope SAO RAS in the period 2009-2014

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