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

Physical Review D (Impact Factor: 4.64). 09/2010; 82(7):072003. DOI: 10.1103/PhysRevD.82.072003
Source: arXiv


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 $E^2 \phi_{\nu_e+\nu_\mu+\nu_\tau}\simeq 1.4 \times 10^{-6}$
GeV cm$^{-2}$ sec$^{-1}$ sr$^{-1}$ for neutrinos in the energy range from
$3\times10^7$ to $3\times10^9$ GeV.

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Available from: Keiichi Mase
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