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arXiv · 0812.4582

Correlated variability in the blazar 3C 454.3

E. W. Bonning·C. Bailyn·C. M. Urry·M. Buxton·G. Fossati·L. Maraschi·P. Coppi·R. Scalzo·J. Isler·A. Kaptur
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Abstract

The blazar 3C 454.3 was revealed by the Fermi Gamma-ray Space Telescope to be in an exceptionally high flux state in July 2008. Accordingly, we performed a multi-wavelength monitoring campaign on this blazar using IR and optical observations from the SMARTS telescopes, optical, UV and X-ray data from the Swift satellite, and public-release gamma-ray data from Fermi. We find an excellent correlation between the IR, optical, UV and gamma-ray light curves, with a time lag of less than one day. The amplitude of the infrared variability is comparable to that in gamma-rays, and larger than at optical or UV wavelengths. The X-ray flux is not strongly correlated with either the gamma-rays or longer wavelength data. These variability characteristics find a natural explanation in the external Compton model, in which electrons with Lorentz factor gamma~10^(3-4) radiate synchrotron emission in the infrared-optical and also scatter accretion disk or emission line photons to gamma-ray energies, while much cooler electrons (gamma~10^(1-2)) produce X-rays by scattering synchrotron or other ambient photons.

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E. W. Bonning, C. Bailyn, C. M. Urry, M. Buxton, G. Fossati, L. Maraschi, P. Coppi, R. Scalzo, J. Isler, A. Kaptur. 2008-12-30. Correlated variability in the blazar 3C 454.3. https://doi.org/10.1088/0004-637x%2F697%2F2%2Fl81

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