SIMBAD references

Multimessenger astronomy offers a powerful approach to studying high-energy radiative processes in astrophysical sources. A notable example was seen in 2017, when the IceCube Neutrino Observatory detected a high-energy neutrino event that was found to coincide with a gamma-ray flare from a blazar. Since then, numerous multimessenger studies combining neutrino and photon data have been conducted, yet the origin of neutrinos from active galactic nuclei (AGN) remains uncertain. In this work, we present the results of an X-ray observing program targeting two AGNs, NGC 1068 and PKS 1502+106. The multiwavelength dataset includes new observations from NICER and NuSTAR from the observing proposal, along with gamma-ray data collected using Fermi-LAT, and one archival observation from Chandra. Additionally, we derive the neutrino fluxes for both AGNs using 10 yr of IceCube data and neutrino spectra predicted by theoretical models. These results demonstrate the importance of combining multimessenger data in building and constraining theoretical models. They also highlight the importance of testing model predictions against observational data to refine measurements of both the neutrino flux and spectral shape.