大质量恒星演化的若干问题(英文)

大质量恒星由于其高光度、短寿命和质量损失 ,对星系的积分光谱能量分布和重元素增丰起主导作用 ,从而在研究星系的形成和演化上具有特殊的意义。特别是随着天文设备的长足进展 ,我们可以回溯宇宙演化的历史 ,得到形成初期时星系的观测性质。那时 ,大质量恒星主导星系的辐射性质 ,这更加突出了对大质量恒星进一步了解的迫切性。但是大质量恒星的演化性质相对中小质量恒星而言 ,有很多不确定性。本文通过对比现有恒星模型与实测结果 ,对现有大质量恒星演化理论中存在的几个与对流和质量损失相关的问题进行了评述 ,并对从理论上 ,特别是通过数字模拟方法对这些问题进行诊断提出了展望。

SELECTED PROBLEMS ON THE EVOLUTION OF MASSIVE STARS

Due to their high luminosity, short life time and feeding back processes by mass loss and SN explosion, massive stars dominate the luminosity and chemical enrichment process at the early evolutionary stages of galaxies, therefore are very important for the studies of the structure and evolution of galaxies. Owing to the recent developments in astrophysical instrumentation, it becomes possible to look further back into the early epoch of galaxy formation when massive stars dominate the radiation properties, and this in turn puts a great emphasis on the study of massive stars. In the theory of stellar structure and evolution, massive stars are far less understood compared with their low mass counterparts. Especially, observations of super giants in our own and nearby galaxies have shown that the current theoretical scenario of massive star evolution is far from satisfactory. A few selected problems concerning convection and mass loss processes are reviewed in this paper, future perspectives using multi dimensional simulation are proposed.