08 September 2010
A search for extremely high energy cosmic neutrinos has been carried out with the IceCube Neutrino Observatory. The main signals in the search are neutrino-induced energetic charged leptons and their rate depends on the neutrino-nucleon cross section. The upper-limit on the neutrino flux has implications for possible new physics beyond the standard model such as the extra space-time dimension scenarios which lead to a cross section much higher than the standard particle physics prediction. In this study we constrain the neutrino-nucleon cross section at energies beyond \(10^9\) GeV with the IceCube observation. The constraints are obtained as a function of the extraterrestrial neutrino flux in the relevant energy range, which accounts for the astrophysical uncertainty of neutrino production models.