Abstract: After the IceCube Neutrino Observatory discovered an isotropic flux of high-energy astrophysical neutrinos, the next fundamental question arose, “Where are these neutrinos coming from?” After a decade, we have now started having our first answers, and neutrino astronomy is emerging among the major players in the multimessenger paradigm. The blazar TXS 0506+056 and the Seyfert galaxy NGC 1068 are the first candidates as extragalactic neutrino sources. Even though they are both AGN powered by a supermassive black hole, they inhabit different regions of the neutrino energy spectrum, with TXS 0506+056 showing a hard spectral emission around the PeV and NGC 1068 exhibiting a softer spectrum at ~1-15 TeV. This suggests that more than one population of accelerators might produce the observed isotropic cosmic neutrino background. In this seminar, I will outline the challenges faced by the searches for neutrino point-like sources with IceCube. I will give an overview of the latest results from searches trying to identify more neutrino sources among blazars and Seyfert galaxies and how much these two populations of sources could contribute to the total neutrino flux observed by IceCube.
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