Mass Loss From Cool Stars: Stellar and Galactic Evolution

目前天文学研究的一个重要领域是研究红巨星在“行星状星云”阶段演化成白矮星时的质量损失。现在人们认为，这种损失是由于原子粒子的风造成的。这种风的强度在几千年的过程中不断增加，直到恒星的包层在非常快的风中以极快的速度剥离。首席调查员(PI)建议继续之前对这一现象的研究，方法是使用一种方法来确定红巨星的大样本中在风中损失的质量，这是根据它们周围星云物质中两条一氧化碳发射线的强度来确定的。质量损失量将与已知的恒星参数相关联，如恒星质量、光度、半径和化学成分，以便建立一个经验模型，说明在这一关键的短暂演化阶段质量是如何损失的。

An important area of current astronomical research concerns the study of mass loss of red giant stars as they evolve to white dwarfs through the "planetary nebula" stage. It is now believed that this loss occurs as a wind of atomic particles. The intensity of this wind increases over the course of several thousand years until the envelope of the star is peeled off in a very fast wind at a rapid rate. The Principal Investigator (PI) proposes to continue previous studies of this phenomenon by using a determining the amount of mass lost in this wind in a large sample of red giants from the strength of two carbon monoxide emission lines in the nebular material surrounding them. The amounts of mass loss will be correlated against known stellar parameters such as stellar mass, luminosity, radius, and chemical composition to permit an empirical model to be developed as to how mass is lost during this critical brief stage of evolution.