Ultra-high energy Neutrinos from Centaurus A and the Auger hot spot

TL;DR

This paper explores Centaurus A as a potential source of ultra-high energy neutrinos, predicting detectable event rates for IceCube and emphasizing the importance of multi-messenger astronomy.

Contribution

It presents a model linking UHECRs from Centaurus A to expected neutrino fluxes, highlighting the role of upcoming gamma-ray observations in multi-messenger studies.

Findings

Predicted neutrino detection rate of 0.4-0.6 events per year above 100 TeV.

Uncertainty mainly due to limited knowledge of source parameters.

Future gamma-ray data will refine neutrino flux predictions.

Abstract

The Pierre Auger collaboration has reported a correlation between Ultra-High Energy Cosmic Rays (UHECR) and nearby Active Galactic Nuclei (AGNs) within 75 Mpc. Two of these events fall within 3 degrees from Centaurus A, the nearest AGN, clearly suggesting that this object is a strong UHECR emitter. Here we pursue this hypothesis and forecast the expected rate of ultra-high energy neutrinos in detectors like IceCube. In our baseline model we find a rate of 0.4--0.6 yr^-1 events above a threshold of 100 TeV, the uncertainty of which is mainly related to the poor knowledge of the physical parameters of the source and on the details of the model. This situation will improve with detailed high energy gamma ray measurements of Cen A by the upcoming GLAST satellite. This would make Cen A the first example where the potential of high energy multi-messenger astronomy is finally realized.