Revealed by Their Own Dust: Identifying the Missing Links in Massive Star Evolution

PI和他的团队将对附近星系中的发光尘埃大质量恒星进行调查，以回答恒星演化的许多问题。我们感兴趣的恒星处于大质量恒星演化的后期，它们的质量正逐渐流失到周围的环境中。它们包括被称为亮蓝变星（LBV）的天体，超巨星B[e]，一些沃尔夫-拉叶星和红超巨星。这项工作的主要目标是更好地理解大质量恒星如何失去质量，特别是间歇性地失去质量，这是恒星演化理论中突出的开放问题之一。研究人员将使用来自斯皮策太空望远镜的存档图像和新的地面光谱学以及光学和近红外波长的成像，为至少20个星系的相关恒星编制彩色星等图。这些测量结果将用于回答许多问题，包括：中红外过剩是否是LBV的良好标志；LBV的质量损失是多少？S主要是偶发的；大规模抛射事件发生的频率是多少？所有的大质量恒星都经历过这样的爆发吗？除了上述主要科学目标之外，该项目还将涉及一名博士后学者，以及已经参与研究的研究生和本科生，从而产生广泛的影响。此外，PI将向公众发布数据，并有一个公共宣传组成部分，支持珀金斯天文台每月的公开讲座。一旦詹姆斯·韦伯太空望远镜（JWST）投入使用，这个项目的结果将对天文学家具有重要的补充价值。

The PI and his team will conduct a survey of luminous dusty massive stars in nearby galaxies in order to answer many questions of stellar evolution. The stars of interest are in the late stages of massive stellar evolution and are losing mass to their environment. They include objects known as luminous blue variables (LBV), supergiant B[e], some Wolf-Rayet stars and red supergiants. The main goal of this work is to better understand how massive stars lose mass, especially episodically, is one of the outstanding open problems in stellar evolution theory. The researchers will use archived images from the Spitzer Space Telescope and new ground-based spectroscopy and imaging at optical and near-infrared wavelengths to compile color-magnitude diagrams for relevant stars in at least 20 galaxies. The measurements will be used to answer many questions, including: is a mid-infrared excess is a good marker of an LBV; is mass loss from LBV?s mostly episodic; what is the frequency of major mass ejection events; and do all massive stars undergo such outbursts? Beyond the main science goals outlined above, the project will have broad impacts by involving a postdoctoral scholar, and graduate and undergraduate students who are already involved in the research. Also, the PI will release data to the public, and has a public outreach component that supports monthly public lectures at the Perkins Observatory. Results from this project will be of significant complementary value for astronomers once James Webb Space Telescope (JWST) is operational.