IceCube at the Threshold

TL;DR

IceCube has detected high-energy astrophysical neutrinos above 100 TeV, confirming an extraterrestrial origin, but no specific sources have been identified yet, prompting multi-messenger follow-up efforts.

Contribution

This paper reviews IceCube's recent findings of high-energy neutrinos and discusses plans for real-time event publication to enhance source identification.

Findings

Detection of neutrinos above 100 TeV significantly above atmospheric background

No individual neutrino sources identified yet

Ongoing multi-messenger follow-up efforts

Abstract

IceCube has observed neutrinos above 100 TeV at a level significantly above the steeply falling background of atmospheric neutrinos. The astrophysical signal is seen both in the high-energy starting event analysis from the whole sky and as a high-energy excess in the signal of neutrino-induced muons from below. No individual neutrino source, either steady or transient, has yet been identified. Several follow-up efforts are currently in place in an effort to find coincidences with sources observed by optical, X-ray and gamma-ray detectors. This paper, presented at the inauguration of HAWC, reviews the main results of IceCube and describes the status of plans to move to near-real time publication of high-energy events by IceCube.