Long term variability and correlation study of the blazar 3C 454.3 in radio, NIR and optical wavebands

Abstract

We performed a long-term optical (B, V, R bands), infra-red (J and K bands) and radio band (15, 22, 37 GHz band) study on the flat spectrum radio quasar, 3C 454.3, using the data collected over a period of more than 8 years (MJD 54500--57500). The temporal variability, spectral properties and inter-waveband correlations were studied by dividing the available data into smaller segments with more regular sampling. This helped us constrain the size and the relative locations of the emission regions for different wavebands. Spectral analysis of the source revealed the interplay between the accretion disk and jet emission. The source predominantly showed a redder-when-brighter trend, though we observed a bluer-when-brighter trend at high flux levels which could be signatures of particle acceleration and radiative cooling. Significant correlations with near-zero lag were seen between various optical/infra-red bands, indicating that these emission regions are co-spatial. Correlations with a time lag of about 10--100 days are seen between optical/infra-red and radio bands indicating these emissions arise from different regions. We also observe the DCF peak lag change from year to year. We try to explain these differences using a curved jet model where the different emission regions have different viewing angles resulting in a frequency dependent Doppler factor. This variable Doppler factor model explains the variability timescales and the variation in DCF peak lag between the radio and optical emissions in different segments. Lags of 6-180 days are seen between emissions in various radio bands, indicating a core-shift effect

arXiv comment18 pages, 8 figures, 8 tables, accepted for publication in ApJ

References in corpus (48)

• Planck 2013 results. XVI. Cosmological parameters
• Unified Schemes for Radio-Loud Active Galactic Nuclei
• Blazars in the Fermi Era: The OVRO 40-m Telescope Monitoring Program
• Turbulent, Extreme Multi-Zone Model for Simulating Flux and Polarization Variability in Blazars
• Doppler factors, Lorentz factors and viewing angles for quasars, BL Lacertae objects and radio galaxies
• Gamma-ray Light Curves and Variability of Bright Fermi-Detected Blazars
• Generating artificial light curves: Revisited and updated
• SMARTS optical and infrared monitoring of 12 gamma-ray bright blazars
• Jet opening angles and gamma-ray brightness of AGN
• On the Reliability of Cross Correlation Function Lag Determinations in Active Galactic Nuclei
• Fermi Gamma-ray Space Telescope Observations of the Gamma-ray Outburst from 3C 454.3 in November 2010
• 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
• Fermi Gamma-ray Space Telescope Observations of Recent Gamma-ray Outbursts from 3C 454.3
• A method for the estimation of the significance of cross-correlations in unevenly sampled red-noise time series
• The awakening of BL Lacertae: observations by Fermi, Swift, and the GASP-WEBT
• The Outburst of the Blazar S5 0716+71 in 2011 October: Shock in a Helical Jet
• Radio/gamma-ray time delay in the parsec-scale cores of active galactic nuclei
• Swift and infra-red observations of the blazar 3C~454.3 during the giant X-ray flare of May 2005
• Search for the shortest variability at gamma rays in flat-spectrum radio quasars
• Significant core shift variability in parsec-scale jets of active galactic nuclei
• A new activity phase of the blazar 3C 454.3. Multifrequency observations by the WEBT and XMM-Newton in 2007-2008
• Multiwavelength observations of 3C 454.3. III. Eighteen months of AGILE monitoring of the "Crazy Diamond"
• Correlated variability in the blazar 3C 454.3
• The correlated optical and radio variability of BL Lacertae. WEBT data analysis 1994-2005
• The radio delay of the exceptional 3C 454.3 outburst. Follow-up WEBT observations in 2005-2006
• Optical and Near Infrared Monitoring of the Black-Hole X-ray Binary GX 339-4 During 2002-2010
• INTEGRAL observations of the blazar 3C454.3 in outburst
• Location of Gamma-ray emission and magnetic field strengths in OJ 287
• Multiwavelength Intraday Variability of the BL Lac S5 0716+714
• The core shift effect in the blazar 3C 454.3
• Multiwavelength Cross-Correlations and Flaring Activity in Bright Blazars
• A connection between $\gamma$-ray and parsec-scale radio flares in the blazar 3C 273
• Multiwavelength Variability of the Blazars Mrk 421 and 3C 454.3 in the High-State
• The high activity of 3C 454.3 in autumn 2007. Monitoring by the WEBT during the AGILE detection
• The long-term optical spectral variability of BL Lacertae
• A rapid and dramatic outburst in Blazar 3C 454.3 during May 2005 - Optical and infrared observations with REM and AIT
• Variability in Active Galactic Nuclei from Propagating Turbulent Relativistic Jets
• 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
• The nature of optical and near-infrared variability of BL Lacertae
• Locating the gamma-ray emission site in Fermi/LAT blazars. II Multifrequency correlations
• Multi-wavelength Temporal Variability of the Blazar 3C 454.3 during 2014 Activity Phase
• Serendipitous VLBI detection of rapid, large-amplitude, intraday variability in QSO 1156+295
• The presence of interstellar scintillation in the 15 GHz interday variability of 1158 OVRO-monitored blazars
• Jets, black holes and disks in blazars
• The Size of IDV Jet Cores

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• Long term optical and infrared variability characteristics of Fermi Blazars
• Gamma-Ray Flares in Long Term Light Curve of 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
• Optical Variability of Three Extreme TeV Blazars
• Mid-infrared Variability of gamma-ray emitting blazars
• Correlation between optical and $\gamma$-ray flux variations in BL Lacs
• Optical Spectral Variations of a Large Sample of Fermi Blazars
• The optical spectral features of 27 Fermi blazars
• Time variability of the core-shift effect in the blazar 3C 454.3
• Multi Frequency Temporal and Spectral variability study of Blazar PKS 1424-418
• Multi-wavelength temporal variability of the blazar PKS 1510-089
• Revisiting radio variability of the blazar 3C 454.3
• Optical monitoring in southern blazars. Analysis of variability and spectral colour behaviours
• Multiband Optical Variability of the Blazar 3C 454.3 on Diverse Timescales
• On the origin of multifrequency temporal and spectral variability in Ton 599
• Multiwavelength Variability Analysis of the Blazar PKS 0727-11: A $\sim$168 Days Quasi-periodic Oscillation in Gamma-ray