15.05.2013
IceCube: First evidence of astrophysical high-energy neutrinos
The IceCube collaboration reported significant progress in their search for astrophysical neutrinos at the IceCube Particle Astrophysics (IPA) conference at the University of Wisconsin in Madison, USA. The detector IceCube recorded twenty-eight events with energies above 30 trillion electronvolts (TeV) between May 2010 and May 2012 including two neutrino events with energies above 1 quadrillion electronvolt (TeV, whereupon 1 PeV equals 1000 TeV), 1000 times higher than any neutrino produced by a man-made accelerator. According to preliminary investigations, these 28 events are not compatible with the present expectations for terrestrial processes producing neutrinos, indicating an excess with respect to these expectations. The first hints of high-energy neutrinos came with the unexpected discovery in May 2012 of two events above 1 PeV. An analysis of those events was first presented at the international conference Neutrino Physics and Astrophysics 2012 in Kyoto and reported last month in a publication submitted to Physical Review Letters. The intensified search presented today turned up 26 additional events exceeding 30 TeV. "This is a magic moment for high energy neutrino astronomy", says Prof. Dr. Elisa Resconi from the Physics Department of the Technische Universität München. "I am personally very proud of this collaborative achievement and aware that much more has to be done before establishing a new type of astronomy. This is just the very first step and we should be very careful on the interpretation.“
The IceCube Neutrino Observatory was put into operation in the antarctic ice in 2010. In a volume of a cubic kilometre, high-energy neutrinos are to be registered which react with elementary particles of ice, whereby electrons, muons and tauons are produced. They are detected via photomultipliers. The IceCube project is operated by an international collaboration of 250 physicists and engineers from the USA, Germany, Sweden, Belgium, UK, Switzerland, Japan, Canada, New Zealand, and Australia. Full information including details of the analysis will be released in a couple of weeks when a paper is submitted to a refereed journal.
Further information:
Ergebnisse von IceCube, IPA 2013, 15.05.2013
Previous publication:
First observation of PeV-energy neutrinos with IceCube, arXiv:1304.5356
Contact:
Prof. Dr. Elisa Resconi
Experimental Physics with Cosmic Particles (ECP)
Technische Universität München
Boltzmannstrasse 2
85748 Garching
Tel. +49 89 35831 7120
E-Mail: elisa.resconi@tum.de
Press contact:
Petra Riedel
Exzellenzcluster Universe
Technische Universität München
Boltzmannstr. 2
85748 Garching
Tel. +49 89 35831 7105
E-Mail: petra.riedel@universe-cluster.de
- Cherenkov photons produced by 100 TeV muon propagating in IceCube. Only 0.01% of all the photons are shown. (Courtesy Dr. Claudio Copper, IceCube)
