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