Urry, C. Megan
Bonning, Erin, Urry, C. Megan, Bailyn, Charles, et al.. "SMARTS OPTICAL AND INFRARED MONITORING OF 12 GAMMA-RAY BRIGHT BLAZARS." The Astrophysical Journal, 756, (2012) 13-29. http://dx.doi.org/10.1088/0004-637X/756/1/13.
We present multiwavelength data for 12 blazars observed from 2008 to 2010 as part of an ongoing optical–infrared
photometric monitoring project. Sources were selected to be bright, southern (δ < 20◦) blazars observed by the
Fermi Gamma-Ray Space Telescope. Light curves are presented for the 12 blazars in BVRJK at near-daily cadence.
We find that optical and infrared fluxes are well correlated in all sources. Gamma-ray bright flat spectrum radio
quasars (FSRQs) in our sample have optical/infrared emission correlated with gamma-rays consistent with inverse
Compton-scattering models. In FSRQs, variability amplitude increases toward IR wavelengths, consistent with the
presence of a thermal accretion disk varying on significantly longer timescales than the jet. In BL Lac objects,
variability is mainly constant, or increases toward shorter wavelength. FSRQs have redder optical–infrared colors
when they are brighter,whileBLLac objects showno such trend. Several objects showcomplicated color–magnitude
behavior: AO 0235+164 appears in two different states depending on its gamma-ray intensity. OJ 287 and 3C 279
show some hysteresis tracks in their color–magnitude diagrams. Individual flares may be achromatic or otherwise
depart from the trend, suggesting different jet components becoming important at different times. We present a
time-dependent spectral energy distribution of the bright FSRQ 3C 454.3 during its 2009 December flare, which is
well fit by an external Compton model in the bright state, although day-to-day changes pose challenges to a simple
one-zone model. All data from the SMARTS monitoring program are publicly available on our Web site.
SMARTS OPTICAL AND INFRARED MONITORING OF 12 GAMMA-RAY BRIGHT BLAZARS
The Astrophysical Journal
|dc.subject.keyword||black hole physics – BL Lacertae objects
general – galaxies
active – galaxies
jets – quasars
The American Astronomical Society