The Role of Stochastic Acceleration in the Prompt Emission of Gamma-Ray
  Bursts: Application to Hadronic Injection
  We study effects of particle re-acceleration (or heating) in the post-shock
region via magnetohydrodynamic/plasma turbulence, in the context of a mixed
hadronic-leptonic model for the prompt emission of gamma-ray bursts (GRBs),
using both analytical and numerical methods. We show that stochastically
accelerated (or heated) leptons, which are injected via pp and pg reactions and
subsequent pair cascades, are plausibly able to reproduce the Band function
spectra with alpha~1 and beta~2-3 in the ~MeV range. An additional hard
component coming from the proton-induced cascade emission is simultaneously
expected, which is compatible with observed extra power-law spectra far above
the MeV range. We also discuss the specific implications of hadronic models for
ongoing high-energy neutrino observations.
