Double pulses and cascades above 2 PeV in IceCube

The IceCube collaboration has seen an unexpected population of high energy neutrinos compatible with an astrophysical origin. We consider two categories of events that can help to diagnose cosmic neutrinos: double pulse, which may allow us to clearly discriminate the cosmic component of ; and cascades with deposited energy above 2 PeV, including events produced by ⎯⎯⎯ at the Glashow resonance, which can be used to investigate the neutrino production mechanisms. We show that one half of the double pulse signal is due to the neutrinos spectral region already probed by IceCube. By normalizing to HESE data, we find that 10 more years are required to obtain 90 % probability to observe a double pulse. The cascades above 2 PeV provide us a sensitive probe of the high energy tail of the neutrino spectrum and are potentially observable, but even in this case the dependence on type of the source is mild. In fact we find that pp or mechanisms give a difference in the number of cascades above 2 PeV of about 25 %, which can be discriminated at 2 in ∼50 years of data taking.