Nucleosynthesis and Chemical Evolution of Galaxies
Nucleosynthesis and Chemical Evolution of Galaxies
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DOI：
10.1007/978-94-009-7183-7_6
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发表时间：
1983
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影响因子：
--
通讯作者：
J. Audouze
中科院分区：
文献类型：
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作者：
J. Audouze
这一章简要介绍了形成所观察到的化学元素的核合成过程：大爆炸之后发生的原始核合成，形成了D、3 He、4 He和至少部分7 Li;银河宇宙射线对星际介质的轰击，形成了大量Li、Be、B元素;以及负责形成较重核素的恒星核合成。这些元素的丰度随着时间的推移而变化，并且在不同的天体物理位置可能有所不同。本文阐述了星系化学演化的基本原理，并介绍了有关这一问题的最新研究成果。评述了星系中金属的随机富集、~（7）Li丰度随时间的演化、外部气体的注入对银盘演化的影响、利用行星状星云推断低质量恒星星星形成速率的尝试等。最后对星系核合成和化学演化的研究前景进行了展望。
This chapter deals with a brief presentation of the nucleosynthesis processes which are responsible for the formation of the observed chemical elements : the primordial nucleosynthesis occurring just after the Big Bang, responsible for the formation of D,3He,4He and at least in part7Li; the bombardment of the interstellar medium by galactic cosmic rays responsible for the formation of the bulk of the Li, Be, B elements; and the stellar nucleosynthesis responsible for the formation of the heavier nuclear species.The abundances of these elements evolve with time and can be different from an astrophysical site to another. The principles which govern the chemical evolution of galaxies are stated herein, and the recent works concerning this problem are mentioned. The stochastic metal enrichement in galaxies, the evolution of the7Li abundance with time, the effect of the infall of external gas on the evolution of the galactic disk, the use of planetary nebulae to try to deduce the rate of star formation for low mass stars etc… are reviewed. Finally the future of the studies concerning the nucleosynthesis and the chemical evolution galaxies is discussed.