2-10 Direct Measurement of the Main s-process Neutron Source

• 作者: Chen Han Chen Xiongjun Chen Zhijun Huang Hanxiong Jiang Liyang Li Kuoang Ren Jie Ruan Xuchao Tang Xiaodong the JUNA collaboration Wang Shuo Zhang Ningtao
• 来源期刊: 中国科学院近代物理研究所和兰州重离子研究装置年报：英文版
• 学科: 物理学
• 关键词: DIRECT MEASUREMENT NEUTRON
• 年，卷（期）: 2014,（1）
• 页码范围: 41-42
• 页数: 2页
• 分类号: O4

摘要

The 13C(, n)16O reaction is the key neutron source reaction for the main s-process nucleosynthesis[1]. Theimportant energy range (Gamow window) for the 13C( , n)16O reaction during the s-process spans from 140 to230 keV in the center of mass frame. Because of the Coulomb barrier, the cross sections drop exponentially asmeasurement approaches the Gamow window energies. Limited by cosmic ray background and the available beamintensity, the ground-based measurements are limited to energies above 280 keV. Therefore, the extrapolationbased on R-matrix calculation and/or in-direct measurement is the current method to estimate the cross sectionsfor astrophysical interest with limited precision. Moreover, due to the existence of sub-threshold resonances, thereare rather large uncertainties associated with the extrapolated cross sections which limit the precision of the currentreaction rate and thus prevent us from a complete understanding of the nucleosynthesis of heavy elements.