The detection of an astrophysical flux of neutrinos in the TeV–PeV energy range by the IceCube Neutrino Observatory has opened new possibilities for the study of extreme cosmic accelerators. The apparent isotropy of the neutrino arrival directions favors an extragalactic origin for this flux, potentially created by a large population of distant sources. Recent evidence for the detection of neutrino emission from extragalactic sources includes the active galaxies TXS 0506+056 and NGC 1068. We here review the current status of the search for the sources of the high-energy neutrino flux, concentrating on its extragalactic contribution. We discuss the implications of these observations for multimessenger studies of cosmic sources and present an outlook for how additional observations by current and future instruments will help address fundamental questions in the emerging field of high-energy neutrino astronomy.

中文翻译：

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高能河外中微子天体物理学

IceCube中微子天文台对TeV-PeV能量范围内的中微子天体物理通量的探测为极端宇宙加速器的研究开辟了新的可能性。中微子到达方向的明显各向同性有利于这种通量的起源于河外，可能是由大量遥远的源产生的。最近探测到河外中微子发射的证据包括活跃星系 TXS 0506+056 和 NGC 1068。我们在这里回顾一下寻找高能中微子通量来源的现状，重点关注其河外贡献。我们讨论了这些观测对宇宙源多信使研究的影响，并展望了当前和未来仪器的额外观测将如何帮助解决新兴的高能中微子天文学领域的基本问题。