Multi-messenger studies of point sources of cosmic rays using data from IceCube

Deutsches Elektronen-Synchrotron DESY
Platanenallee 6
D-15738 Zeuthen

Humboldt-Universität zu Berlin
Institut für Physik
Newtonstraße 15
12489 Berlin

The goal of this research proposal is the discovery of individual sources of high energy cosmic neutrinos with IceCube. Such a discovery will contribute to the understanding of the origin, propagation and nature of the high energy cosmic rays. Neutrinos can escape from dense matter regions and propagate freely over cosmological distances. Gamma-rays with energies up to a few tens TeV are detected from several astrophysical objects. On the other hand, charged hadrons are observed up to energies of a few hundreds EeV. Remarkably, even after almost hundred years since the discovery of cosmic rays, the very nature of the high energy processes which led to these experimental results is in most cases not understood. The elusive nature of neutrinos makes them rather unique astronomical messengers. Moreover, their detection will provide the proof of the hadronic nature of the accelerating objects.

While it has been realized for many decades that the case for neutrino astronomy is compelling, detectors with sensitivities sufficient to detect predicted fluxes are going to become available only know. The AMANDA experiment at the South Pole has passed an interesting milestone: Known sources of high energy gamma-rays could become observable in neutrinos if the number of gamma-rays and neutrinos are roughly equal. Within the next three years, the IceCube array combined with the existing AMANDA detector will reach sensitivities an order of magnitude better than we have today and reach the potential to observe high energy neutrino emission from Active Galactic Nuclei or Gamma Ray Bursts.

In astronomy, the discovery potential is increased by multi-wavelength observations. Many high energy gamma-ray sources would not have been identified without observations at lower energies (like X-rays or radio-waves). Many astronomical objects have been successfully observed in worldwide “multi-wavelength” campaigns yielding a more complete view. The central idea of the present application is to extend the multi-wavelength concept to neutrinos, becoming more generally a “multi-messenger” approach. This would dramatically increase the discovery potential of IceCube, confirm the hadronic nature of the cosmic accelerator, and allow to trigger observations with electromagnetic waves by neutrino signals, i.e. providing a clear “hadron trigger”.

The DESY group in Zeuthen is leading the point source search with AMANDA, having produced the sky-map with the highest neutrino statistics ever. The observations have motivated new search strategies which are a central part of the activities proposed for the Helmholtz group. This group will be linked to the high energy gamma-ray astronomy projects H.E.S.S. and MAGIC at the Humboldt University, making Berlin/Zeuthen a particularly promising place for multi-messenger studies. Results from other gamma-ray telescopes around the world together with X-ray and radio measurements will be used for a better selection of sources candidates and possible high-state periods of these objects, notably in close collaboration with groups from the Astrophysical Institute in Potsdam.

Leader of the Young Investigators Group of Helmholtz:

Dr. E. Bernardini
Deutsches Elektronen-Synchrotron
Platanenallee 6
D-15738 Zeuthen
Office: 2A/01
Tel. : +49 337627-7483
Email :

Weiterführende Links
application/pdf Sachbericht 2006 (249KB)
application/pdf Sachbericht 2007 (51KB)
application/pdf Sachbericht 2008 (1.3 MB)
application/pdf Sachbericht 2009 (997KB)
application/pdf Sachbericht 2010 (622KB)
application/pdf Schlussbericht 2012 (872KB)