She-Sheng Xue

We study the Compton-rocket effect of multi-photon interacting with electrons in an opaque fireball (or fire spot) of photons and $e^-e^+$ pairs at temperature $T_γ\gg m_e$. We find the charged-particle acceleration and the avalanche runaway process, leading to a non-trivial probability of ultra-high-energy (UHE) electrons and protons, which subsequently produce very-high-energy (VHE) photons and neutrinos. We show such peculiar dynamics using the Gamma-Ray Burst central engine fireball, whose inner part inflows and forms a gravitationally trapped fireshell (halo) around a black hole. The halo is a metastable, cooling via UHE particle emissions and blackbody radiation. We calculate the UHE particle luminosity varying in time, and discuss the peculiar features of such produced UHE particles, which lead to VHE particles, in connection with possible numerical simulations, observations and experiments.