High energy neutrino emission from the earliest gamma-ray bursts

We discuss the high energy neutrino emission from gamma-ray bursts resulting from the earliest generation ("population III") stars forming in the Universe, whose core collapses into a black hole. These gamma-ray bursts are expected to produce a highly relativistic, magnetically dominated jet, where protons can be accelerated to ultrahigh energies. These interact with the photons produced by the jet, leading to ultrahigh energy photomeson neutrinos as well as secondary leptons and photons. The photon luminosity and the shock properties, and thus the neutrino spectrum, depend on the mass of the black holes as well as on the density of the surrounding external gas. We calculate the individual source neutrino spectral fluxes and the expected diffuse neutrino flux for various source parameters and evolution scenarios. Both the individual and diffuse signals appear detectable in the 1-300 PeV range with current and planned neutrino detectors such as IceCube and ARIANNA, provided the black hole mass is in excess of 30-100 solar masses. This provides a possible test for the debated mass of the progenitor stellar objects, as well as a probe for the early cosmological environment and the formation rate of the earliest structures.