The Role in Interstellar Dust Production by Type II Supernovae and Red Supergiants

对原始星系(红移大于5)的观测表明，它们含有大量的尘埃。这些星系中的恒星很年轻(年龄不到10亿年)，因此尘埃不能归因于渐近巨型分支恒星或Ia型超新星，这两者都需要更长的时间才能发展/演化到尘埃产生阶段。然而，大质量恒星(红色超巨星和II型超新星)产生的尘埃可能解释了这些星系的高尘埃含量。然而，人们对这些物体中尘埃的形成知之甚少。这个为期三年的项目将试图描述由大质量恒星在局部宇宙中产生的尘埃的特征，特别是解决关键问题，即II型超新星和红超巨星是否单独产生原始星系中所见的尘埃量。这里将用近红外和中红外测光技术模拟大小麦哲伦星云中大样本红超巨星的中等分辨率光谱，以揭示其潜在的光谱能量分布和随波长变化的红化。还将汇编第二类超新星的后期观测(光谱和光度学)的重要样本，并将确定这些天体产生的尘埃的数量和性质。我们将使用蒙特卡罗辐射传输程序、最大熵和多层球面方法来研究这种尘埃的组成、粒度分布、消光和再发射特性。这些结果有望增进我们对超新星和红超巨星通过尘埃的产生和分布，在大爆炸后形成的第一批星系的形成和演化中所扮演的角色的了解。由于这些结果将在更广泛的天文学社区产生广泛影响，数据和模型将在一个网站上公开提供。该程序将有助于规划未来仪器的观测，如阿塔卡马大毫米阵列和詹姆斯·韦伯空间望远镜。这些望远镜的首要科学目标之一是详细研究高红移星系及其尘埃含量。博士后研究人员和研究生都将通过这个项目接受培训。有关尘埃研究的讨论也将包括在路易斯安那州立大学学习社区的S教授的天文学/科幻小说课程中。

Observations of primordial (redshift greater than five) galaxies have shown that they contain large amounts of dust. The stars in these galaxies are young (ages less than one billion years), so the dust cannot be attributed to asymptotic giant branch stars or Type Ia supernovae, both of which take longer to develop/evolve to dust producing stages. However, dust produced by massive stars (red supergiants and Type II supernovae) may explain the high dust content of these galaxies. Yet very little is known about dust formation in these objects. This three-year project will attempt to characterize the dust produced by massive stars in the local universe and, in particular, address the key question as to whether the Type II supernovae and red supergiant stars alone could produce the amount of dust seen in primordial galaxies.Here, moderate resolution spectra of large samples of red supergiants in the Large and Small Magellanic Clouds with near- and mid-infrared photometry will be modeled to reveal their underlying spectral energy distribution and wavelength dependent reddening. A significant sample of late-time observations (spectra and photometry) of type II supernovae will also be compiled and the amount and nature of the dust production by these objects will be determined. The composition, size distribution, extinction, and re-emission properties of this dust will be studied using Monte Carlo radiative transfer codes, maximum entropy, and multilayer sphere methods. These results are expected to advance our knowledge of the role supernovae and red supergiants play, via dust production and distribution, in the formation and evolution of the first galaxies formed after the big bang. As these results will have a broad impact in the wider astronomical community, the data and models will be made publicly available on a website. This program will be useful in planning observations for future instruments such as The Atacama Large Millimeter Array and the James Webb Space Telescope. Among the high priority science goals of these telescopes is the detailed study of high-redshift galaxies and their dust content. Both a postdoctoral researcher and a graduate student will be trained through this project. Discussion of this research on dust will also be included in Dr. Clayton''s team-taught astronomy/science fiction course at the LSU Learning Community.