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arXiv · 2410.14079

PKS 2254+074: A Blazar in Likely Association with the Neutrino Event IceCube-190619A

Shunhao Ji·Zhongxiang Wang
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Abstract

We report our study of the field of a $\simeq$0.2 PeV neutrino event IC-190619A. This neutrino belongs to Gold events, which more likely have an astrophysical origin. Among the two $\gamma$-ray sources within the neutrino's positional uncertainty region, we find that one of them, the BL-Lac--type blazar PKS~2254+074, had a $\gamma$-ray flare at the arrival time of the neutrino. The flare is determined to have lasted $\sim$2.5 yr in a 180-day binned light curve, constructed from the data collected with the Large Area Telescope (LAT) onboard {\it the Fermi Gamma-ray Space Telescope (Fermi)}. Accompanying the flare, optical and mid-infrared brightening is also seen. In addition, $\geq$10 GeV high energy photons from the source have been detected, suggesting a hardening of the emission during the flare. Given both the positional and temporal coincidence of PKS~2254+074 with IC-190619A, we suggest that this blazar is likely another member of a few recently identified (candidate) neutrino-emitting blazars.

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Shunhao Ji, Zhongxiang Wang. 2024-10-17. PKS 2254+074: A Blazar in Likely Association with the Neutrino Event IceCube-190619A. https://arxiv.org/abs/2410.14079

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