The Dust Enrichment of Galaxies

星际尘埃在星系的演化中起着关键作用，特别是在恒星形成过程中。在其AGB红巨星演化阶段，低质量和中等质量恒星被认为是像我们所在的星系的星际尘埃预算的重要贡献者。然而，大质量恒星及其核心塌缩(CC)超新星可能会对一些星系的尘埃预算做出重大贡献，特别是在它们演化的早期阶段。在许多高Z星系中观察到的大量尘埃不被认为是由低质量和中等质量恒星产生的，因为1 Gyr或更少的星系年龄太短，不可能有大量的AGB恒星存在。大质量恒星和它们的CC SNE，来自为这些星系提供能量的恒星爆发，是它们最有可能的尘埃来源。这项提议寻求从2009年9月起将目前的PDRA赠款续期三年，以便利用为与赫歇尔、斯皮策和HST进行的空间研究分配的大量时间。这些观测，再加上最佳的数据整理程序和适当的辐射传输模型，就能够量化高质量恒星和低质量恒星对不同类型星系尘埃浓缩率的贡献。

Interstellar dust plays a key role in the evolution of galaxies, particularly during the star formation process. During their AGB red giant phase of evolution, low and intermediate mass stars are known to be important contributors to the interstellar dust budgets of galaxies like our own. However, massive stars, and their core-collapse (CC) supernovae, could potentially make a significant contribution to the dust budgets of some galaxies, particularly during their earliest stages of evolution.The copious amounts of dust observed in many high-z galaxies are not believed to be produced by low and intermediate mass stars, since the galaxy ages of 1 Gyr or less are too short for significant numbers of AGB stars to be present. Massive stars, and their CC SNe, arising from the starbursts that power these galaxies, are the most plausible sources of their dust. This proposal seeks to renew a current PDRA grant for three years, from September 2009, in order to exploit significant time allocations that have been made for spaceborne studies with Herschel, Spitzer and the HST. These observations, coupled with optimal data reduction procedures and appropriate radiative transfer modelling, can enable a quantification of the contributions of high mass stars and of lower mass stars to the dust enrichment rates of different galaxy types.