The Evolution of Massive Stars as a Function of Metallicity: Closing the Loop Observationally in the Local Group

大质量恒星的演化作为金属丰度的函数：在本星系群中闭合观测环虽然大质量恒星很罕见，但它们的重要性远远超过它们稀少的数量。通过它们强烈的外流风的作用和它们最终以超新星的形式爆炸毁灭，它们为星际介质提供了大量的能量输入。它们的寿命很短，只有几百万年，质量损失率很高，是星系中重元素富集的主要来源。梅西博士目前正在结束对本星系群附近星系中的红超巨星、蓝超巨星和沃尔夫-拉叶星的调查。该项目计划在本日历年内完成。现在需要进行后续观测，在这项新奖励涵盖的期间，将用大型望远镜观察在调查中发现的恒星，以获得光谱和光度测定。它将有可能了解大质量恒星的演化是如何随着质量、年龄和重元素含量的变化而变化的，而不需要过去困扰这类研究的观测偏差。

"The Evolution of Massive Stars as a Function of Metallicity: Closing the Loop Observationally in the Local Group"AST- 0093060Although massive stars are rare, they have an importance far beyond their scant numbers. Through action of their strong outflowing winds and their eventual explosive destruction as supernovae, they provide much of the energy input into the interstellar medium. With short lifetimes of only a few million years and high mass-loss rates, they are primary sources of heavy element enrichment in a galaxy. Dr. Massey is presently concluding a survey for red supergiant, blue supergiant and Wolf-Rayet stars in nearby galaxies of the Local Group. This project is scheduled for completion during the current calendar year. Follow-up observations are now required and, during the period covered by this new award, stars found in the survey will be observed with large telescopes to obtain spectra and photometry. It will be possible to learn how the evolution of massive stars varies with mass, age and heavy element content without the observational biases that have plagued this type of investigation in the past.