1210.0647 (Bing Zhang et al.)

Model-dependent high-energy neutrino flux from Gamma-Ray Bursts    [PDF]

Bing Zhang, Pawan Kumar

The IceCube Collaboration recently reported a stringent upper limit on the high energy neutrino flux from GRBs, which provides a meaningful constraint on the standard internal shock model. Recent broad band electromagnetic observations of GRBs also challenge the internal shock paradigm for GRBs, and some competing models for gamma-ray prompt emission have been proposed. We describe a general scheme for calculating the GRB neutrino flux, and compare the predicted neutrino flux levels for different models. We point out that the current neutrino flux upper limit already disfavors any dissipative photosphere model that invokes high energy proton acceleration at the same site, and challenges the internal shock model. If the neutrino flux upper limit continues to go down in the next few years, then it would suggest that the GRB emission site is at a larger radius than the internal shock radius or for some reason protons do not get accelerated to high energies at the site where gamma-ray photons are produced. The larger-radius solution for the low neutrino flux from GRBs would provide support to magnetic dissipation models that invoke a large dissipation radius, such as the ICMART model.

View original: http://arxiv.org/abs/1210.0647