Radio detection of Neutrinos


      After the success of IceCube, especially at detecting neutrinos at the astrophysical energy frontier, eyes are pointed at even higher energies. At those energies the expected flux of neutrinos that result from interactions of cosmic rays with the cosmic microwave background is at least two orders of magnitude smaller than the measured flux. In order to have a realistic chance of detecting those cosmogenic neutrinos, detectors of an effective volume of 100 times that of the already impressive 1 cubic kilometer of IceCube are needed.

      While optical sensors such as deployed in IceCube deliver impressive results, the attenuation length of the ice sets a cost-prohibitive limit to the size of a detector equipped with photo sensors.
      However, an interaction of a neutrino is not only followed by a flash of light that is measured by IceCube, but also by a short radio pulse. The attenuation length of radio signals in the ice is more than 500 meters, which means that radio antennas can be deployed sparsely and still instrument massive volumes.

      The international community is gearing up to start building a large radio array. Most of the previous efforts such as the pilot-arrays ARA and ARIANNA were US lead. With the DFG funded Emmy-Noether group of Anna Nelles, DESY is now one of the first European groups to push the international effort of building a large radio array.