Search for high-energy neutrino emission from hard X-ray AGN with IceCube

TL;DR

This study uses 12 years of IceCube data to search for high-energy neutrinos from hard X-ray AGN, testing their role as cosmic-ray accelerators and neutrino sources.

Contribution

It presents the first comprehensive search for neutrino emission from hard X-ray AGN using a stacked and point source analysis with extensive IceCube data.

Findings

No significant neutrino signal detected from the AGN sample.

Constraints placed on the neutrino flux from hard X-ray AGN.

Implications for models of cosmic-ray acceleration in AGN.

Abstract

Active Galactic Nuclei (AGN) are powerful astronomical objects with very high luminosities. Theoretical arguments suggest that these objects are capable of accelerating particles to energies of 10$^{20}$ eV. In environments with matter or photon targets, cosmic-ray interactions transpire leading to the production of pionic gamma rays and neutrinos. Since the AGN environment is rich in gas, dust and photons, they are promising candidate sources of high-energy astrophysical neutrinos. While the neutrinos manage to escape, the gamma rays may further interact and cascade down to hard X-rays in environments with sufficiently large photon or gas targets. We have used 12 years of IceCube data to perform a stacked search and a point source search for high-energy neutrino emission from hard X-ray AGN sampled from $\textit{Swift}$-BAT Spectroscopic Survey (BASS) and present the results of these two analyses.