Icecube Nondetection of Gamma-Ray Bursts: Constraints on the Fireball Properties

Abstract

The increasingly deep limit on the neutrino emission from gamma-ray bursts (GRBs) with IceCube observations has reached the level that could put useful constraints on the fireball properties. We first present a revised analytic calculation of the neutrino flux, which predicts a flux an order of magnitude lower than that obtained by the IceCube collaboration. For benchmark model parameters (e.g. the bulk Lorentz factor is Γ = 10 2.5 , the observed variability time for long GRBs is t ob v = 0.01s and the ratio between the energy in accelerated protons and in radiation is η p = 10 for every burst) in the standard internal shock scenario, the predicted neutrino flux from 215 bursts during the period of the 40-string and 59-string configurations is found to be a factor of ∼ 3 below the IceCube sensitivity. However, if we accept the recently found inherent relation between the bulk Lorentz factor and burst energy, the expected neutrino flux increases significantly and the spectral peak shifts to lower energy. In this case, the non-detection then implies that the baryon loading ratio should be η p 10 if the variability time of long GRBs is fixed to t ob v = 0.01s. Instead, if we relax the standard internal shock scenario but keep to assume η p = 10, the non-detection constrains the dissipation radius to be R 4 × 10 12 cm assuming the same dissipation radius for every burst and benchmark parameters for fireballs. We also calculate the diffuse neutrino flux from GRBs for different luminosity functions existing in the literature. The expected flux exceeds the current IceCube limit for some luminosity functions, and thus the non-detection constrains η p 10 in such cases when the variability time of long GRBs is fixed to t ob v = 0.01s.

Neutrinos from Gamma Ray Bursts in the IceCube and ARA Era

“…IceCube reported no detection of any GRB-associated neutrino in a data set taken from April 2008 to May 2010 [34]; None of the high energy neutrinos reported for the next two years [35] is GRB-associated either, and as far as we know no neutrino event has been associated with any GRB to date. This non-detection is in conflict with earlier models [22,24,[36][37][38], all of which predicted the detection of approximately ten GRB neutrinos by IceCube during this period. Those earlier estimates were largely calibrated based on the fireball hypothesis, and were motivated by the assumption that UHECRs are produced .…”

Ultrahigh-energy cosmic ray production by turbulence in gamma-ray burst jets and cosmogenic neutrinos

“…Owing to the hard spectrum, the spectral peak at ∼ 10 20 eV becomes higher than that for the shock model. To take into account the diversity of Γ, we also adopt an empirical relation between Γ and L γ expressed by Γ = 72.1L 0.49 52 , which was adopted in He et al [21] based on the results of Ghirlanda et al [75]. This relation leads to a slightly softer spectrum, as shown by the model B in Fig.…”

Search for muon neutrinos from gamma-ray bursts with the ANTARES neutrino telescope using 2008 to 2011 data

“…Owing to these effects, the doubly peaked structure of the spectrum from muon and pion decays now features an additional high-energy component from K + decays. Moreover, the authors discussed several problems with the older neutrino flux estimations, such as using the real average photon energy instead of the peak energy of the photon distribution, taking the full width of the ∆-resonance into account, and simulating the energy losses of secondary particles as well as the energy dependence of the mean free path of protons (see also He et al 2012). The combination of all these effects gives rise to a prediction for the neutrino yield that is about one order of magnitude below the result of Guetta et al (2004).…”