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arXiv · 1807.08816

Multi-messenger observations of a flaring blazar coincident with high-energy neutrino IceCube-170922A

The IceCube·Fermi-LAT·MAGIC·AGILE·ASAS-SN·HAWC·H. E. S. S·INTEGRAL·Kanata·Kiso·Kapteyn·Liverpool telescope·Subaru·Swift/NuSTAR·VERITAS·VLA/17B-403 teams
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Abstract

Individual astrophysical sources previously detected in neutrinos are limited to the Sun and the supernova 1987A, whereas the origins of the diffuse flux of high-energy cosmic neutrinos remain unidentified. On 22 September 2017 we detected a high-energy neutrino, IceCube-170922A, with an energy of approximately 290 TeV. Its arrival direction was consistent with the location of a known gamma-ray blazar TXS 0506+056, observed to be in a flaring state. An extensive multi-wavelength campaign followed, ranging from radio frequencies to gamma-rays. These observations characterize the variability and energetics of the blazar and include the first detection of TXS 0506+056 in very-high-energy gamma-rays. This observation of a neutrino in spatial coincidence with a gamma-ray emitting blazar during an active phase suggests that blazars may be a source of high-energy neutrinos.

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The IceCube, Fermi-LAT, MAGIC, AGILE, ASAS-SN, HAWC, H. E. S. S, INTEGRAL, Kanata, Kiso, Kapteyn, Liverpool telescope, Subaru, Swift/NuSTAR, VERITAS, VLA/17B-403 teams. 2018-07-23. Multi-messenger observations of a flaring blazar coincident with high-energy neutrino IceCube-170922A. https://doi.org/10.1126/science.aat1378

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