General Physics Physics Seminar 16 January 2003
Simulations of Relativistic Astrophysical Flows
Jeroen Bergmans and Bram Achterberg (Astronomical Institute, Utrecht, NL)
Daniel van Odyck and Barry Koren (CWI, Amsterdam, NL)
Rony Keppens (FOM Instituut voor Plasmafysica Rijnhuizen,
Nieuwegein, NL
Gamma-ray bursts constitute the most energetic events in the
observable universe so far. Their nature is still a mystery, but the
energy and timescales suggest that the source must be accompanied by
an extremely relativistic explosion or jet flow. Relativistic jets are
also found in active galaxies and quasars. The structure and behavior
of all these objects is characterized by sharp discontinuities or
shocks in the flow.
To numerically model these phenomena both accurate representation of
the shocks (small scales) as well as the global flow pattern are
required. The aim is to combine shock-capturing methods for the
relativistic fluid equations with an adaptive mesh refinement
algorithm to bridge the large range of length scales involved.