Johnson Jennifer A
Department of Astronomy and Center for Cosmology and AstroParticle Physics, Ohio State University, Columbus, OH, USA.
Science. 2019 Feb 1;363(6426):474-478. doi: 10.1126/science.aau9540. Epub 2019 Jan 31.
Elements heavier than helium are produced in the lives and deaths of stars. This Review discusses when and how the process of nucleosynthesis made elements. High-mass stars fuse elements much faster, fuse heavier nuclei, and die more catastrophically than low-mass stars. The explosions of high-mass stars as supernovae release elements into their surroundings. Supernovae can leave behind neutron stars, which may later merge to produce additional heavy elements. Dying low-mass stars throw off their enriched outer layers, leaving behind white dwarfs. These white dwarfs may also later merge and synthesize elements as well. Because these processes occur on different time scales and produce a different pattern of elements, the composition of the Universe changes over time as stars populate the periodic table.
比氦重的元素是在恒星的诞生与消亡过程中产生的。本综述讨论了核合成过程产生元素的时间和方式。大质量恒星比小质量恒星更快地融合元素,融合更重的原子核,并且死亡方式更具灾难性。大质量恒星作为超新星爆发,将元素释放到周围环境中。超新星爆发后可能会留下中子星,这些中子星随后可能合并产生更多重元素。即将死亡的小质量恒星会抛射出富含元素的外层,留下白矮星。这些白矮星之后也可能合并并合成元素。由于这些过程发生在不同的时间尺度上,产生不同的元素模式,随着恒星填充元素周期表,宇宙的组成会随时间而变化。