Speaker: Hans Niederhausen (Michigan State University)
Title: High Energy Astrophysics with IceCube: Evidence for neutrino emission from the nearby activegalaxy NGC 1068
Abstract:
The IceCube Neutrino Observatory, deployed beneath the South Pole, is the largest optical neutrinotelescope in the World. IceCube has been measuring a diffuse flux of high-energy (TeV and above)astrophysical neutrinos for almost a decade. The sources of the vast majority of these neutrinosremain elusive, but studies indicate that gamma-ray obscured sources may at least in parts beresponsible. Most recently, IceCube reported strong evidence for TeV neutrino emission from NGC1068, a well-known and nearby active galaxy. I will explain how IceCube searches for neutrinos fromastrophysical sources and how recent improvements in our analysis methods enabled this result.When put into the multi-messenger context, in particular the non-detection of TeV gamma-rays bythe MAGIC telescopes, this measurement suggests that the gamma-ray obscured vicinity of thecentral supermassive black hole acts as a cosmic hadron accelerator. The next steps are clear. Bystudying similar objects we may finally identify a class of sources that makes a sizeable contributionto the diffuse flux of astrophysical neutrinos.