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arXiv · 1902.09077

Multi-wavelength variability of CGRaBS J0733+0456: identifying a distant $\gamma$-ray blazar at z = 3.01

Neng-Hui Liao·Li-Ming Dou·Ning Jiang·Yi-Bo Wang·Yi-Zhong Fan·Ting-Gui Wang
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Abstract

We report on OVRO, WISE, Swift and Fermi-LAT observations of the high redshift blazar CGRaBS J0733+0456, from which significant flux variations in radio, infrared (IR) as well as $\gamma$-ray domains are detected. Particularly, the amplitude of long-term IR variation is over one order of magnitude and the IR variability timescale can be constrained as short as a few hours in the source frame. The IR and $\gamma$-ray light curves are found to be rather similar, and the strong quasi-simultaneous infrared and $\gamma$-ray flares are proved to be unique among the nearby $\gamma$-ray sources. This is the first time to identify a $\gamma-$ray blazar at redshift $z\geq 3$ with multi-wavelength flux variations (flares). Broadband spectral energy distributions in different flux states are constructed and theoretically described. The $\gamma-$ray flares from some blazars as distant as redshift $\sim$ 5 are expected to be detectable for Fermi-LAT.

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Neng-Hui Liao, Li-Ming Dou, Ning Jiang, Yi-Bo Wang, Yi-Zhong Fan, Ting-Gui Wang. 2019-02-25. Multi-wavelength variability of CGRaBS J0733+0456: identifying a distant $\gamma$-ray blazar at z = 3.01. https://doi.org/10.3847/2041-8213/ab2893

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