Multiband Optical Variability of the Blazar 3C 454.3 on Diverse Timescales

Abstract

Due to its peculiar and highly variable nature, the blazar 3C 454.3 has been extensively monitored by the WEBT team. Here, we present for the first time these long-term optical flux and color variability results using data acquired in B, V, R, and I bands over a time span of $\sim$ 2 decades. We include data from WEBT collaborators and public archives such as SMARTS, Steward Observatory, and ZTF. The data are binned and segmented to study the source over this long term when more regular sampling was available. During our study, the long-term spectral variability reveals a redder when brighter (RWB) trend, which, however, stabilizes at a particular brightness cutoff $\sim$ 14.5 mag in the I-band, after which it saturates and evolves into a complex state. This trend indicates increasing jet emission dominance over accretion disk emission until jet emission completely dominates. Plots of the spectral index variation (following $F_{\nu }\propto {\nu }^{-\alpha }$) reveal a bimodal distribution using a one-day binning. These correlate with two extreme phases of 3C 454.3, an outburst or high flux state and quiescent or low flux state, which are respectively jet and accretion disk dominated. We have also conducted intra-day variability studies of nine light curves and found that six of them are variable. Discrete Correlation Function (DCF) analysis between different optical waveband pairs peak at zero lags, indicating co-spatial emission in different optical bands.

arXiv comment18 pages, 6 figures, 5 tables

References in corpus (60)

• Unified Schemes for Radio-Loud Active Galactic Nuclei
• The Zwicky Transient Facility: System Overview, Performance, and First Results
• A Unifying View of the Spectral Energy Distributions of Blazars
• The Spectral Energy Distribution of Fermi bright blazars
• BL Lac Objects in the Synchrotron Proton Blazar Model
• Internal shocks in the jets of radio-loud quasars
• Modeling the Emission Processes in Blazars
• SMARTS optical and infrared monitoring of 12 gamma-ray bright blazars
• Flaring Behavior of the Quasar 3C~454.3 across the Electromagnetic Spectrum
• Blazar spectral variability as explained by a twisting inhomogeneous jet
• A Tight Connection between Gamma-Ray Outbursts and Parsec-Scale Jet Activity in the Quasar 3C 454.3
• The unprecedented optical outburst of the quasar 3C 454.3. The WEBT campaign of 2004-2005
• The WEBT BL Lac Campaign 2000
• Multi-colour optical monitoring of eight red blazars
• Early Fermi Gamma-ray Space Telescope Observations of the Quasar 3C 454.3
• Fermi Gamma-ray Space Telescope Observations of Recent Gamma-ray Outbursts from 3C 454.3
• The WEBT BL Lacertae Campaign 2001 and its extension
• A new activity phase of the blazar 3C 454.3. Multifrequency observations by the WEBT and XMM-Newton in 2007-2008
• Correlated variability in the blazar 3C 454.3
• Near Infrared Intraday Variability of Mrk 421
• Flare-like variability of the Mg IIλ2800Å emission line in the gamma-ray blazar 3C 454.3
• The brightest gamma-ray flaring blazar in the sky: AGILE and multi-wavelength observations of 3C 454.3 during November 2010
• Multiwavelength Variations of 3C 454.3 during the November 2010 to January 2011 Outburst
• Optical Flux and Spectral Variability of Blazars
• The radio delay of the exceptional 3C 454.3 outburst. Follow-up WEBT observations in 2005-2006
• The GASP-WEBT monitoring of 3C 454.3 during the 2008 optical-to-radio and gamma-ray outburst
• The long-lasting activity of 3C 454.3. GASP-WEBT and satellite observations in 2008-2010
• Multiwavelength Variability of the Blazars Mrk 421 and 3C 454.3 in the High-State
• Multi-band optical variability of three TeV Blazars on Diverse Timescales
• The high activity of 3C 454.3 in autumn 2007. Monitoring by the WEBT during the AGILE detection
• A rapid and dramatic outburst in Blazar 3C 454.3 during May 2005 - Optical and infrared observations with REM and AIT
• On the July 2007 flare of the blazar 3C 454.3
• An Optical-Near-Infrared Outburst with No Accompanying Gamma-Rays in the Blazar PKS 0208-512
• On the reliability of microvariability tests in quasars
• Gamma-ray Flux Distribution and Non-linear behavior of Four LAT Bright AGNs
• The dual nature of blazar fast variability. Space and ground observations of S5 0716+714
• Nature of Intra-night Optical Variability of BL Lacertae
• A Time Resolved Study of the Broad Line Region in Blazar 3C 454.3
• A Consolidated Framework of the Color Variability in Blazars: Long-Term Optical/Near-Infrared Observations of 3C 279
• A peculiar multi-wavelength flare in the Blazar 3C 454.3
• Multiband Photopolarimetric Monitoring of the Outburst of the Blazar 3C~454.3 in 2007
• Long term variability and correlation study of the blazar 3C 454.3 in radio, NIR and optical wavebands
• Testing microvariability in quasar differential light curves using several field stars
• Multi-band optical-NIR variability of blazars on diverse timescales
• Intra-night optical variability characteristics of different classes of narrow line Seyfert 1 galaxies
• Long-term optical-infrared color variability of blazars
• Optical Flux and Spectral Variability of the TeV blazar PG 1553+113
• Multi-wavelength Temporal Variability of the Blazar 3C 454.3 during 2014 Activity Phase
• The optical behaviour of BL Lacertae at its maximum brightness levels: a blend of geometry and energetics
• Long term optical and infrared variability characteristics of Fermi Blazars
• Modeling the Broadband Emission of 3C 454.3
• Intranight variability of 3C 454.3 during its 2010 November outburst
• Blazar 3C 454.3 in Outburst and Quiescence During 2005-2007: Two Variable Synchrotron Emission Peaks
• Long-term optical spectroscopic variations in blazar 3C 454.3
• Multiwavelength analysis and the difference in the behavior of the spectral features during the 2010 and 2014 flaring periods of the blazar 3C 454.3
• Relativistic Doppler beaming and misalignments in AGN jets
• Optical Variability of Three Extreme TeV Blazars
• Detecting microvariability in type 2 quasars using enhanced F-test
• Extremely high polarization in 2010 outburst of blazar 3C 454.3
• The spectral variability of FSRQs

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