Fission cycling in a supernova r process
Fission cycling in a supernova r process
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超新星过程中的裂变循环
DOI：
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发表时间：
2007
期刊：
影响因子：
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通讯作者：
W. Hix
中科院分区：
文献类型：
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作者：
J. Beun;G. McLaughlin;R. Surman;W. Hix
最近的晕星丰度观测显示了一个对r过程有重要影响的重要特征：在第二和第三个峰值之间存在一个主要的r过程，这在晕星之间是一致的。我们探索了裂变循环和稳定的{beta}流作为这一特征背后的驱动机制。R过程中裂变循环的存在可以解释第二和第三个峰之间的核合成产额，而稳定的{beta}流的存在可以解释一致的r过程模式，在天体物理条件的微小变化下是稳健的。我们利用核坍缩超新星的中微子驱动风来研究裂变循环和r过程中稳定的{beta}流。由于传统的中微子驱动风模型不能产生这些机制所需的非常丰富的中子条件，我们研究了在中微子驱动风环境中发生裂变循环所必需的中微子物理变化，并探索在什么条件下获得稳定的{beta}流。
Recent halo star abundance observations exhibit an important feature of consequence to the r process: the presence of a main r process between the second and third peaks that is consistent among halo stars. We explore fission cycling and steady {beta} flow as the driving mechanisms behind this feature. The presence of fission cycling during the r process can account for nucleosynthesis yields between the second and third peaks, whereas the presence of steady {beta} flow can account for consistent r-process patterns, robust under small variations in astrophysical conditions. We employ the neutrino-driven wind of the core-collapse supernova to examine fission cycling and steady {beta} flow in the r process. As the traditional neutrino-driven wind model does not produce the required very neutron-rich conditions for these mechanisms, we examine changes to the neutrino physics necessary for fission cycling to occur in the neutrino-driven wind environment, and we explore under what conditions steady {beta} flow is obtained.