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arXiv · 2003.06405

3HSP J095507.9+355101: a flaring extreme blazar coincident in space and time with IceCube-200107A

P. Giommi·P. Padovani·F. Oikonomou·T. Glauch·S. Paiano·E. Resconi
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Abstract

The uncertainty region of the highly energetic neutrino IceCube200107A includes 3HSP J095507.9+355101 ($z$~=~0.557), an extreme blazar, which was detected in a high, very hard, and variable X-ray state shortly after the neutrino arrival. Following a detailed multi-wavelength investigation, we confirm that the source is a genuine BL Lac, contrary to TXS 0506+056, the first source so far associated with IceCube neutrinos, which is a "masquerading" BL Lac. As in the case of TXS0506+056, 3HSP J095507.9+355101 is also way off the so-called "blazar sequence". We consider 3HSP J095507.9+355101 a possible counterpart to the IceCube neutrino. Finally, we discuss some theoretical implications in terms of neutrino production.

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P. Giommi, P. Padovani, F. Oikonomou, T. Glauch, S. Paiano, E. Resconi. 2020-03-13. 3HSP J095507.9+355101: a flaring extreme blazar coincident in space and time with IceCube-200107A. https://doi.org/10.1051/0004-6361%2F202038423

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