Stellar evolution at high mass including the effect of a stellar wind
Stellar evolution at high mass including the effect of a stellar wind
复制标题
高质量恒星演化，包括恒星风的影响
DOI：
10.1086/157388
复制
发表时间：
1979
期刊：
影响因子：
--
通讯作者：
C. Chin
中科院分区：
文献类型：
--
作者：
R. Stothers;C. Chin
从零年龄主序列到核心氦燃烧结束，计算了15-120M/次太阳/因恒星风而发生质量损失的恒星的演化轨迹。所有模型都是基于Cox-Stewart不透明度的，并充分考虑了内部结构的半对流和对流变化。已经考虑了各种质量损失的情况。如果假定主序列上的质量损失量很小，则主序列后的径迹对对流采用Schwarzschild或Ledoux准则，以及对初始金属丰度和对流混合长度采用什么值非常敏感。假设较大的主序质量损失量必然会产生红色超巨星(由于氢壳层对流的抑制)，而在主序或主序后阶段假设较大的质量损失量将总是产生蓝色氦星(由于大部分氢包层的去除)。将理论得出的结果与OBN星、WN星和明亮的超巨星的观测结果进行比较，表明最大质量的恒星在其一生中可能会损失更多的质量。然而，对于初始质量略低的恒星的解释则比较模糊，除了质量损失对于初始质量低于约30米/次太阳/的恒星来说可能并不是很重要。
Evolutionary tracks for stars of 15--120 M/sub sun/ undergoing mass loss due to a stellar wind have been computed from the zero-age main sequence to the end of core helium burning. All the models are based on Cox-Stewart opacities, and take fully into account semiconvective and convective modifications of the interior structure. Various cases of mass loss have been considered. If the amount of mass loss on the main sequence is assumed to be small, the post--main-sequence tracks turn out to be very sensitive to whether the Schwarzschild or the Ledoux criterion for convection is adopted, as well as to what values are adopted for the initial metals abundance and convective mixing length. A somewhat larger assumed amount of main-sequence mass loss invariably will produce a red supergiant (due to the suppression of hydrogen-shell convection), while a very much larger assumed amount of mass loss during either the main-sequence or post--main-sequence stages will always produce a blue helium star (due to removal of most of the hydrogen envelope). Comparison of the theoretically derived results with observations of OBN stars, WN stars, and bright supergiants suggests that the most massive stars could, in the course of their lifetimes, lose a substantialmore » amount of mass. However, the interpretation for stars of slightly lower initial mass is rather more ambiguous, except that mass loss is probably not very important for initial masses below approx.30 M/sub sun/.« less