The Cycle of Dust in the Milky Way: Clues from the High-Redshift and Local Universe

Abstract

Models for the evolution of dust are used to show that the observed trend of the abundance of polycyclic aromatic hydrocarbons (PAHs) with metallicity is the result of the delayed injection of carbon dust that formed in low mass asymptotic giant branch (AGB) stars into the interstellar medium. We also use our dust evolution models to examine the origin of dust at redshifts > 6, when only supernovae and their remnants could have been, respectively, their sources of production and destruction. Unless an average supernova (or its progenitor) produces between 0.1 and 1 Msun of dust, alternative sources will need to be invoked to account for the massive amount of dust observed at these redshifts.

16 pages, 9 figures. To be published in the Heidelberg 2008 Conference on "Cosmic Dust Near and Far"