The first search for extremely-high energy cosmogenic neutrinos with the IceCube Neutrino Observatory

Abstract

We report on the results of the search for extremely-high energy (EHE) neutrinos with energies above $10^7$ GeV obtained with the partially ($\sim$30%) constructed IceCube in 2007. From the absence of signal events in the sample of 242.1 days of effective livetime, we derive a 90% C.L. model independent differential upper limit based on the number of signal events per energy decade at $E^2\ddot{I}{•}_{\hat{I}{½}_e+\hat{I}{½}_{\hat{I}}¼+\hat{I}{½}_{\ddot{I}}„}\simeq 1.4\times 10^{-6}$ GeV cm${}^{-2}$ sec${}^{-1}$ sr${}^{-1}$ for neutrinos in the energy range from $3\times 10^7$ to $3\times 10^9$ GeV.

11 pages, 6 figures, 4 tables, accepted for publication in Physical Review D