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arXiv · 1805.07765

$Fermi$-LAT detection of a transient $\gamma$-ray source in the direction of a distant blazar B3 1428+422 at $z =4.72$

Neng-Hui Liao·Shang Li·Yi-Zhong Fan
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Abstract

We report the detection of a transient $\gamma$-ray source in the direction of B3 1428+422 ($z=4.72$) by analyzing the 110-month {\it Fermi}-LAT Pass 8 data. The new transient $\gamma-$ray source is far away from the Galactic plane and has a rather soft spectrum, in agreement with being a high redshift blazar. We suggest that the newly discovered transient is the $\gamma$-ray counterpart of B3 1428+422, which could be the {\it most distant} GeV source detected so far. The detection of a group of such distant $\gamma-$ray blazars will be helpful to reconstruct the evolution of the luminosity function and to study the extragalactic background light at such high redshifts.

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Neng-Hui Liao, Shang Li, Yi-Zhong Fan. 2018-05-20. $Fermi$-LAT detection of a transient $\gamma$-ray source in the direction of a distant blazar B3 1428+422 at $z =4.72$. https://doi.org/10.3847/2041-8213/aae20d

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