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تسجيل مستخدم جديدPre-burst neutrinos of gamma-ray bursters accompanied by high-energy photons
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Previous researches on high-energy neutrino events from gamma-ray bursters (GRBs) suggest a neutrino speed variation $v(E)=c(1pm E/E^{ u}_{mathrm{LV}})$ with ${E}^{ u}_{rm LV}=(6.4pm 1.5)times10^{17}~{ rm GeV}$, together with an intrinsic time difference ${Delta {t}_{rm in}=(-2.8pm 0.7)times10^2~{rm s}}$, 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 $1.07~rm{TeV}$ 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.
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Previous researches on high-energy photon events from gamma-ray bursts~(GRBs) suggest a light speed variation $v(E)=c(1-E/E_{mathrm{LV}})$ with $E_{mathrm{LV}}=3.6times10^{17}~mathrm{ GeV}$, together with a pre-burst scenario that hight-energy photon
s come out about 10 seconds earlier than low-energy photons at the GRB source. However, in the Lorentz invariance violating scenario with an energy dependent light speed considered here, high-energy photons travel slower than low-energy photons due to the light speed variation, so that they are usually detected after low-energy photons in observed GRB data. Here we find four high-energy photon events which were observed earlier than low-energy photons from Fermi Gamma-ray Space Telescope~(FGST), and analysis on these photon events supports the pre-burst scenario of high energy photons from GRBs and the energy dependence of light speed listed above.
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