Mass Loss: Its Effect on the Evolution and Fate of High-Mass Stars
Mass Loss: Its Effect on the Evolution and Fate of High-Mass Stars
复制标题
DOI：
10.1146/annurev-astro-081913-040025
复制
发表时间：
2014-02
影响因子：
33.3
通讯作者：
N. Smith
中科院分区：
文献类型：
--
作者：
N. Smith
由于我们对质量损失的看法近期发生了变化，以及对O型星中高双星比例的观测，我们对大质量恒星演化的理解处于不断变化之中。由于团块对观测诊断的影响，热星的标准依赖金属丰度的星风的质量损失率比现代恒星演化代码中采用的速率低2 - 3倍。较弱的热星星风将氢包层去除的责任转移到了演化的超巨星的星风、脉动和爆发，以及双星物质转移上。特别是对剥壳超新星的研究需要双星物质转移。在IIn型超新星中可以看到爆发性质量损失的显著例子，这些超新星在仅仅几年前就抛射出了巨大的壳层。这些爆发是核心坍缩的前奏，可能意味着在最新的核燃烧阶段存在严重的不稳定性。我们面临这样的困境：最重要的质量损失模式也是最不确定的，这削弱了预测能力……
Our understanding of massive star evolution is in flux due to recent upheavals in our view of mass loss and observations of a high binary fraction among O-type stars. Mass-loss rates for standard metallicity-dependent winds of hot stars are lower by a factor of 2–3 compared with rates adopted in modern stellar evolution codes, due to the influence of clumping on observed diagnostics. Weaker hot star winds shift the burden of H-envelope removal to the winds, pulsations, and eruptions of evolved supergiants, as well as binary mass transfer. Studies of stripped-envelope supernovae, in particular, require binary mass transfer. Dramatic examples of eruptive mass loss are seen in Type IIn supernovae, which have massive shells ejected just a few years earlier. These eruptions are a prelude to core collapse, and may signify severe instabilities in the latest nuclear burning phases. We encounter the predicament that the most important modes of mass loss are also the most uncertain, undermining the predictive power...