Multi-color optical monitoring of ten blazars from 2005 to 2011

Abstract

We carried out multi-color optical monitoring of a sample of ten blazars from 2005 to 2011. The sample contains 3 LBLs, 2 IBLs, 4 HBLs, and 1 FSRQ. Our monitoring focused on the long-term variability and the sample included nine BL Lac objects and one flat-spectrum radio quasar. A total number of 14799 data points were collected. This is one of the largest optical database for a sample of ten blazars. All objects showed significant variability except OT 546. Because of the low sampling on each single night, only BL Lacertae was observed to have intra-day variability on 2006 November 6. Most BL Lac objects showed a bluer-when-brighter chromatism, while the flat-spectrum radio quasar, 3C 454.3, displayed a redder-when-brighter trend. The BWB color behaviors of most BL Lacs can be at least partly interpreted by the fact of increasing variation amplitude with increasing frequency observed in these objects. The average spectral index of LBLs is around 1.5, as expected from the model dominated by Synchrotron Self-Compton (SSC) loss. The optical emission of HBL is probably contaminated by the thermal emission from the host galaxies. Correlation analysis did not reveal any time delay between variations at different wavelengths.

arXiv comment19 pages, 6 figures, accepted for publication in ApJS

References in corpus (84)

• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• Unified Schemes for Radio-Loud Active Galactic Nuclei
• A Unifying View of the Spectral Energy Distributions of Blazars
• The Spectral Energy Distribution of Fermi bright blazars
• AGN Black Hole Masses and Bolometric Luminosities
• The Connection between X-ray- and Radio-Selected BL Lacertae Objects
• General physical properties of bright Fermi blazars
• Multi-Epoch VLBA Observations of EGRET-Detected Quasars and BL Lac Objects: Superluminal Motion of Gamma-Ray Bright Blazars
• Multiwavelength Observations of Strong Flares From the TeV-Blazar 1ES 1959+650
• Modeling the Emission Processes in Blazars
• SMARTS optical and infrared monitoring of 12 gamma-ray bright blazars
• Spectral energy distributions of a large sample of BL Lacertae objects
• Jet opening angles and gamma-ray brightness of AGN
• Deep Wide-Field Spectrophotometry of the Open Cluster M67
• HST/COS Observations of the Ly alpha Forest toward the BL Lac Object 1ES1553+113
• Imaging redshifts of BL Lac objects
• The unprecedented optical outburst of the quasar 3C 454.3. The WEBT campaign of 2004-2005
• The WEBT BL Lac Campaign 2000
• The Spectral Energy Distributions of Fermi Blazars
• Multi-colour optical monitoring of eight red blazars
• Photopolarimetric Monitoring of Blazars in the Optical and Near-Infrared Bands with the Kanata Telescope. I. Correlations between Flux, Color, and Polarization
• Synchrotron Self-Compton Model for Rapid Nonthermal Flares in Blazars with Frequency-Dependent Time Lags
• The WEBT BL Lacertae Campaign 2001 and its extension
• The awakening of BL Lacertae: observations by Fermi, Swift, and the GASP-WEBT
• On the masses of black-holes in radio-loud quasars
• The gamma-ray brightest days of the blazar 3C 454.3
• Testing tests on AGN microvariability
• Detection of TeV Gamma Rays from the BL Lac Object 1ES1959+650 with the Whipple 10m Telescope
• Multiwavelength observations of 3C 454.3. III. Eighteen months of AGILE monitoring of the "Crazy Diamond"
• A new activity phase of the blazar 3C 454.3. Multifrequency observations by the WEBT and XMM-Newton in 2007-2008
• Near Infrared Intraday Variability of Mrk 421
• VERITAS Observations of a Very High Energy Gamma-ray Flare from the Blazar 3C 66A
• The optical microvariability and spectral changes of the BL Lacertae object S5 0716+714
• Detection of VHE radiation from the BL Lac PG 1553+113 with the MAGIC telescope
• Optical Flux and Spectral Variability of Blazars
• The black hole mass of BL Lac objects from the stellar velocity dispersion of the host galaxy
• Spectral Slope Variability of BL Lac Objects in the Optical Band
• Evidence for VHE Gamma-ray Emission from the Distant BL Lac PG 1553+113
• The central black hole masses and Doppler factors of the $\gamma$-ray loud blazars
• AGILE detection of a strong gamma-ray flare from the blazar 3C 454.3
• The long-lasting activity of 3C 454.3. GASP-WEBT and satellite observations in 2008-2010
• Infrared Variation of Radio Selected BL Lacertae Objects
• Multi-band optical variability studies of BL Lacertae
• Multi-band optical micro-variability observations of BL Lacertae
• Longterm Optical Monitoring of Bright BL Lacertae Objects with ATOM: Spectral Variability and Multiwavelength Correlations
• Long and short term variability of seven blazars in six near-infrared/optical bands
• Ten-year optical monitoring of PKS 0735+178: historical comparison, multiband behaviour and variability timescales
• Quasi-simultaneous two band optical variability of the blazars 1ES 1959+650 and 1ES 2344+514
• 15 colour photometry of Landolt SA95 standard star field
• Multiwavelength Variability of the Blazars Mrk 421 and 3C 454.3 in the High-State
• Discovery of a very high energy gamma-ray signal from the 3C 66A/B region
• The long-term optical spectral variability of BL Lacertae
• Synchrotron and Synchrotron Self-Compton Spectral Signatures and Blazar Emission Models
• Multiwavelength Observations of 3C 66A during the WEBT campaign of 2003 - 2004
• X-ray/UV/Optical follow-up of the blazar PKS 2155-304 after the giant TeV flares of July 2006
• Long-term monitoring of PKS 0537-441 with Fermi-LAT and multiwavelength observations
• BeppoSAX Spectral Survey of BL Lacs - new spectra and results
• Simultaneous B'V'R' Monitoring of BL Lacertae Object S5~0716+714 and Detection of Inter-Band Time Delay
• The WEBT campaign on the BL Lac object PG 1553+113 in 2013. An analysis of the enigmatic synchrotron emission
• The WEBT Campaign on the Intermediate BL Lac Object 3C66A in 2007-2008
• A Consolidated Framework of the Color Variability in Blazars: Long-Term Optical/Near-Infrared Observations of 3C 279
• Multiband Photopolarimetric Monitoring of the Outburst of the Blazar 3C~454.3 in 2007
• Is BL Lacertae an "orphan" AGN? Multiband and spectroscopic constraints on the parent population
• VERITAS detection of $\gamma$-ray flaring activity from the BL Lac object 1ES 1727+502 during bright moonlight observations
• Rapid optical variability of TeV blazars
• Short Term Flux and Colour Variations in Low-Energy Peaked Blazars
• The optical spectral slope variability of 17 blazars
• Redshift constraints for RGB 0136+391 and PKS 0735+178 from deep optical imaging
• Multi-band optical-NIR variability of blazars on diverse timescales
• Optical Spectroscopy of BL Lac Objects:new redshifts and mis-identified sources
• Long-term optical polarization variability of the tev blazar 1es~1959+650
• Discovery of very high energy gamma-ray emission from the blazar 1ES 1727+502 with the MAGIC Telescopes
• VERITAS Observations of the BL Lac Object PG 1553+113
• Optical Variability and Colour Behaviour of 3C 345
• Intraday Optical Variability of BL Lacertae
• Seven-Year Multi-Color Optical Monitoring of BL Lacertae Object S5 0716+714
• Optical multi-band observations of BL Lacertae during the outburst of 2005
• Unusual optical quiescence of the classical BL Lac object PKS 0735+178 on intranight time scale
• Optical and Radio Variability of BL Lacertae
• Optical and infrared photometry of the blazar PKS0537-441
• Probing the Transition Between the Synchrotron and Inverse-compton Spectral Components of 1ES 1959+650
• The Near-IR-Optical-UV Emission of BL Lacertae Objects
• Long-term optical variability of the blazars PKS 2005-489 and PKS 2155-304
• Variability and spectral variation of 3C 66A

Cited by in corpus (13)

• Long term optical and infrared variability characteristics of Fermi Blazars
• Multi-band behaviour of the TeV blazar PG 1553+113 in optical range on diverse timescales
• A statistical study of the optical spectral variability in gamma-ray blazars
• Multiband optical flux density and polarization microvariability study of optically bright blazars
• The optical spectral features of 27 Fermi blazars
• Optical Spectral Variations of a Large Sample of Fermi Blazars
• Catching profound optical flares in blazars
• Multi-wavelength Variation Phenomena of PKS 0735+178 on Diverse Timescale
• Intra-day variability of BL Lacertae from 2016 to 2018
• Medium-band observation of the neutrino emitting blazar, TXS 0506+056
• Multi-band optical variability on diverse timescales of blazar 1E 1458.8+2249
• Multi-wavelength Optical and NIR Variability Analysis of the Blazar PKS 0027-426
• The intra-day Optical Monitoring of BL Lacerate Object 1ES 1218+304 at Its Highest X-ray Flux Level