Pre-burst neutrinos of gamma-ray bursters accompanied by high-energy photons

Previous researches on high-energy neutrino events from gamma-ray bursters (GRBs) suggest a neutrino speed variation $v\left(E\right)=c(1\pm E/E_{\mathrm{LV}}^{\nu })$ with $E_{\mathrm{LV}}^{\nu }=(6.4\pm 1.5)\times {10}^{17}\text{GeV}$, together with an intrinsic time difference $\Delta t_{\mathrm{in}}=(-2.8\pm 0.7)\times {10}^2\text{s}$, which means that high-energy neutrinos come out about 300 s earlier than low-energy photons in the source reference system. Considering the possibility that pre-bursts of neutrinos may be accompanied by high-energy photons, in this work we search for high-energy photon events with earlier emission time from 100 to 1000 s before low-energy photons at source by analyzing Fermi Gamma-ray Space Telescope (FGST) data. We perform the searching of photon events with energies larger than 100 MeV, and find 14 events from 48 GRBs with known redshifts. Combining these events with a $1.07\text{TeV}$ photon event observed by the Major Atmospheric Gamma Imaging Cherenkov telescopes (MAGIC), we suggest a pre-burst stage with a long duration period of several minutes of high energy neutrino emissions accompanied by high energy photons at the GRB source.