Study of Gamma-Ray Burst Origin from Prompt and Afterglow Modeling

University Of Texas At Austin, Austin TX

Investigators

Abstract

AST-0406878 Panaitescu Advances in understanding Gamma-Ray Bursts in recent years have come from observations of the longer wavelength emission, the afterglow, following the burst. Modeling this radio, optical, and X-ray afterglow has become an essential procedure for obtaining information about the explosion, such as the energy release, the opening angle of the emergent jet, and the density of the surrounding medium. This is a project for extensive development of the theoretical and numerical tools for this modeling, incorporating the hydrodynamical evolution of outflows endowed with angular structure, emission from the reverse shock propagating through ejecta with a non-uniform magnetic field subject to a continuous injection of mass and energy, and various effects on the jet dynamics and emission of the electron-positron pairs created ahead of the forward shock. The work focuses on early afterglows, within one hour of the burst, and involves extensive use of data in the optical, millimeter, and radio bands from a large number of ground-based telescopes. The results will also be useful for studies of pulsar winds and active galactic nuclei, and will help to probe the high redshift Universe and improve predictions of the neutrino fluxes relevant to new large neutrino observatories. Knowledge and insights gained will be included in courses for students and high school teachers, and used in public lectures and other outreach activities.