Theory of high energy emission in GRBs

Gamma-ray bursts are thought to be capable of accelerating cosmic rays up to GZK energies Ep similar to 10(20) eV, leading to a flux at Earth comparable to that observed by large EAS arrays such as AUGER. Both leptonic, e.g. synchrotron and inverse Compton, as well as photomeson processes can lead to GeV-TeV gamma-rays measurable by GLAST, AGILE, or ACTs, providing useful probes of the burst physics and model parameters. Photomeson interactions also produce neutrinos at energies ranging from sub-TeV to EeV, which will be probed with forthcoming experiments such as IceCube, ANITA and KM3NeT. This would provide information about the fundamental interaction physics, the acceleration mechanism, the nature of the sources and their environment.