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arXiv 1907.09178astro-ph.HEnucl-exnucl-th
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核反应截面不确定性对热核超新星中p-核合成的影响

Impact of Uncertainties in Nuclear Reaction Cross Sections on p-Nucleosynthesis in Thermonuclear Supernovae

T. Rauscher, N. Nishimura, G. Cescutti, R. Hirschi, A. St. J. Murphy, C. Travaglio

AI总结:

本文开发蒙特卡洛后处理方法量化核反应率不确定性对核合成丰度的影响,并应用于Ia型超新星中p-核的产生,发现最终丰度不确定性总体较小且主要由高密度区域主导。

摘要:

在核合成模型中,由中子、质子和α粒子引发的反应的反应截面和反应率的不确定性向最终同位素丰度的传播,是核合成和银河系化学演化研究中的一个重要问题。我们开发了一种蒙特卡洛方法,以便对核不确定性对核合成的影响进行大规模后处理研究。该方法采用了结合真实实验和理论不确定性的温度相关反应率不确定性。通过详细的统计分析,最终丰度的不确定性以概率密度分布的形式导出。此外,基于反应率与丰度的相关性,一个自动化程序能够从多个区域或示踪物叠加形成的复杂流动模式中识别出最重要的反应。该方法迄今已应用于多种核合成过程。本文重点关注以热核(Ia型)超新星形式爆炸的白矮星中p-核的产生。我们发现,尽管理论核不确定性占主导地位,最终丰度的不确定性总体上较小。对低密度和高密度区域的单独分析表明,总不确定性主要由高密度区域主导。

英文摘要:

The propagation of uncertainties in reaction cross sections and rates of neutron-, proton-, and alpha-induced reactions into the final isotopic abundances obtained in nucleosynthesis models is an important issue in studies of nucleosynthesis and Galactic Chemical Evolution. We developed a Monte Carlo method to allow large-scale postprocessing studies of the impact of nuclear uncertainties on nucleosynthesis. Temperature-dependent rate uncertainties combining realistic experimental and theoretical uncertainties are used. From detailed statistical analyses uncertainties in the final abundances are derived as probability density distributions. Furthermore, based on rate and abundance correlations an automated procedure identifies the most important reactions in complex flow patterns from superposition of many zones or tracers. The method so far was already applied to a number of nucleosynthesis processes. Here we focus on the production of p-nuclei in white dwarfs exploding as thermonuclear (type Ia) supernovae. We find generally small uncertainties in the final abundances despite of the dominance of theoretical nuclear uncertainties. A separate analysis of low- and high-density regions indicates that the total uncertainties are dominated by the high-density regions.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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