Gamma Ray Bursts and the Fermi Gamma Ray Space Telescope: Notes to the La Plata Lectures

Abstract

Gamma-ray bursts (GRBs) are a mixed class of sources consisting of, at least, the long duration and short-hard subclasses, the X-ray flashes, and the low-luminosity GRBs. In all cases, the release of enormous amounts of energy on a short timescale makes an energetic, relativistic or mildly relativistic fireball that expands until it reaches a coasting Lorentz factor determined by the amount of baryons mixed into the fireball. Radiation is produced when the blast wave interacts with the surrounding medium at an external shock, or when shell collisions dissipate kinetic energy at internal shocks. This series of notes is organized as follows: (1) The observational situation of GRBs is summarized; (2) Progenitor models of GRBs are described; (3) An overview of the the blast-wave physics used to model leptonic emissions is given; (4) GRB physics is applied to hadronic acceleration and ultra-high energy cosmic ray production; (5) Prospects for GRB physics and gamma-ray astronomy with the Fermi Gamma-ray Space Telescope (FGST, formerly GLAST), and space-based and ground-based observatories are considered. Also included are exercises and problems.