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S. H. R. Bank (Towson University), G. C. Clayton (Louisiana State University)
Recent discovery of dust in high red-shift galaxies implies abundant dust production in the Universe as early as approximately 1 billion years after the Big Bang. This conflicts with some current dust formation theories that attribute the production of roughly half of the observed interstellar dust to low mass, evolved, Asymptotic Giant Branch stars (AGBs). Such stars take several billion years to develop. We review the currently discussed possibilities to produce large amounts of interstellar dust on shorter time scales. On a much shorter timescale, Type II, or core-collapse supernovae could theoretically supply the required metallicity, while Type I SNe are ignored because of their longer evolutional lifetime, higher explosion energies, and greater radioactive content, which inhibit dust formation. The first generation of stars known as Population III, being extremely massive (140-260 MSolar) had the capability to produce significant quantities of dust on the required short timescale, when these stars exploded as supernovae. While theory allows for current supernovae to be dust producers, observational evidence is sparse. One of the few instances of dust formation observed in supernova ejecta is that of SN 1987A, which is estimated to have produced from 0.0001 to 1 MSolar of dust. More significant production of dust has recently been suggested by sub-millimeter studies of SN remnant Cas A estimating 0.2 to 4 MSolar of cool (< 20 K) dust. Identifying dust formation in recent supernovae ejecta is difficult since it is hard to distinguish new dust from dust predating the supernova. This project was supported by the NSF/REU grant AST-0097694 and the Nantucket Maria Mitchell Association.
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Bulletin of the American Astronomical Society, 35#5
© 2003. The American Astronomical Soceity.