Chemical evolution with bursts of star formation - Element ratios in dwarf galaxies
Chemical evolution with bursts of star formation - Element ratios in dwarf galaxies
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恒星形成爆发的化学演化——矮星系中的元素比率
DOI：
10.1086/185930
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发表时间：
1991
期刊：
影响因子：
--
通讯作者：
R. Wyse
中科院分区：
文献类型：
--
作者：
G. Gilmore;R. Wyse
研究表明，恒星形成在少量爆发中进行的星系，其化学元素的演化比例与恒星持续形成的星系中的比例非常不同。元素比率与总化学丰度的系统变化在很大程度上由恒星形成爆发的开始和持续时间决定，可能与在太阳附近看到的非常不同。特别是，从LMC场星和星系团的年龄分布推断，当恒星形成以少量相隔很远的爆发进行时，就会自然地发生氧相对于铁的不足，如在大麦哲伦星云中观察到的那样。既不需要引用恒星初始质量函数的变化，也不需要引用金属增强的风。参考文献25。
It is demonstrated that galaxies in which star formation proceeds in a small number of bursts evolve their chemical elements in ratios which are very different from those in galaxies with continuing star formation. Systematic changes of element ratios with overall chemical abundance are determined to a large extent by the onset and duration of the star formation bursts and can be very different from those seen in the solar neighborhood. In particular, it is shown that an underabundance of oxygen relative to iron, such as is observed in the Large Magellanic Cloud, occurs naturally when star formation proceeds in a small number of widely separated bursts, as is inferred from the age distribution of LMC field stars and clusters. There is no need to invoke either variations in the stellar initial mass function or metal-enhanced winds. 25 refs.