Interacademiaal College / Interacademic Course 2009

Gamma-Ray Bursts and Their Host Galaxies

Ralph A.M.J. Wijers and Lex Kaper

Contact and questions: ralph.wijers@uva.nl

Astronomy at Amsterdam

Cartoon from Spui, the UvA alumni magazine, December 2008 issue; copyright: Spui magazine

Gamma-ray bursts were `a riddle wrapped in an enigma' for about 30 years after their discovery in the late 1960s. In 1997, however, the discovery that after the short flash of gamma rays one can observe a fading `afterglow' in all wavelengths for hours to years revolutionised the field. It was quickly discovered that these are the most powerful explosions in the universe, an order of magnitude more energetic than supernovae. Still, like supernovae they mostly seem to originate from the deaths of massive stars. They are a typical astronomical problem: a lot of instrumental progress and phenomenological detective work was needed to uncoover their nature, but once this was done they provide a window on some very peculiar and extreme physics that cannot be tested in the lab. Also, because they are so luminous and thus visible even from high redshift, they hold significant promise as tools for studying the evolution of structure and the star formation history in our universe.

In this class, we shall first discuss the astronomical tools that are used to study GRBs. Then we discuss their astrophysics, which will require the study of relativistic dynamical and radiation processes and astrophysical shocks. We will then move on to discuss what we know about their formation and environment, via the study of their host galaxies. Finally, we will wrap up by examining the state of GRBs as cosmological tools.

Each course day will consist of about 2 hours of lectures and 1.5 hours of problem solving and discussion. Homework will be given.