# Search for GeV γ-Ray Pair Halos Around Low Redshift Blazars.

@article{Chen2015SearchFG,
title={Search for GeV $\gamma$-Ray Pair Halos Around Low Redshift Blazars.},
author={Wenlei Chen and James H. Buckley and Francesc Ferrer},
journal={Physical review letters},
year={2015},
volume={115 21},
pages={
211103
}
}
• Published 28 October 2014
• Physics
• Physical review letters
We report on the results of a search for γ-ray pair halos with a stacking analysis of low redshift blazars using data from the Fermi Large Area Telescope. For this analysis we used a number of a priori selection criteria, including the spatial and spectral properties of the Fermi sources. The angular distribution of ~1 GeV photons around 24 stacked isolated high-synchrotron-peaked BL Lacs with redshift z<0.5 shows an excess over that of pointlike sources. A frequentist test yields a p value of…

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