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Session 15 - Interstellar Medium I.
Display session, Monday, January 15
North Banquet Hall, Convention Center
We present the results of a high resolution 2-D hydrodynamical model designed to study the chemical and dynamical evolution of dwarf irregular galaxies. We examine the effects of the energy and mass injection of supernovae produced by a stellar OB associations, modelling the interstellar medium of dwarf galaxies and tracking the evolution of the resultant ``superbubble'' of hot interstellar gas. Two unique features of our code are the ability to track the cosmic chemical abundances as a function of time and position in a galaxy, and the use of appropriate cooling functions for the low metallicity ambient ISM (Z=0.1 Z_\sun) and the metal-enriched stellar ejecta. We demonstrate what galactic parameters are necessary for such bubbles to ``blow-out'' of the gaseous component of galaxy and parameterize this galactic metal-loss rate as a function of these parameters. This metal loss is potentially important in producing the observed mass-metallicity relation in dwarf irregular galaxies. In addition we couple the hydrodynamical calculations with routines to calculate the spectral emission diagnostics of these superbubbles, generating synthetic X-ray emission maps and spectra for comparison with observations.
Program listing for Monday