Updated Partial Cross Sections of Proton-Nucleus Reactions
Updated Partial Cross Sections of Proton-Nucleus Reactions
复制标题
更新的质子核反应的部分横截面
DOI：
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发表时间：
1998
期刊：
影响因子：
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通讯作者：
A. Barghouty
中科院分区：
文献类型：
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作者：
R. Silberberg;C. Tsao;A. Barghouty
我们利用Webber等人的氢-碳靶的10≤Z≤28核的束的输运协作的氢靶的测量部分截面，更新了1973-1990年的截面计算。对于5≤Z≤28的束流，以及明尼苏达大学-华盛顿大学-加州理工学院合作的Fe、Kr、Ag、La、Ho和Au原子核的束流。我们对截面参数方程进行了18种修正。部分截面的精确值对于评估相对于次级散裂产物具有较小相对丰度的宇宙射线的源成分非常重要，例如13C、14N、18O、25 mg、26 mg和31P。13C/12C、18O/16O、22Ne/20Ne和(25 mg+26 mg)/24 mg的同位素比值受Wolf-Rayet星对宇宙线的贡献影响，而14N特别是H和He则受宇宙线中轻核的抑制影响。P的丰度是区分两个模型的关键：(1)恒星耀斑和(2)增强的非挥发性颗粒溅射物质对宇宙线的贡献。较早的20Ne和24 mg到14N和15N的S截面和T截面增加了1.5倍，这使得计算的N的源组分减少了。早先计算的Au的S和T截面(可能是从铂到铅群)，到具有ΔZ<；23的元素的截面必须减少约15%，而对于最重的核，奇偶Rudstam参数被消除。结果，减少了计算的61；Z<；74的二次分量，并增强了计算的一次分量。这加强了在太阳系丰度之上增加Z>；60的r过程元素的必要性。
We have updated our 1973-1990 cross section calculations by using the measured partial cross sections of the hydrogen target of the transport collaboration for beams of nuclei 10 ≤ Z ≤ 28, of the hydrogen-carbon targets of Webber et al. for beams of 5 ≤ Z ≤ 28, and of the University of Minnesota-Washington University-Caltech collaboration for beams of Fe, Kr, Ag, La, Ho, and Au nuclei. We have developed 18 modifications of equations of cross section parameters. Exact values of partial cross sections are important for evaluating the source composition of cosmic rays that have small relative abundances relative to the secondary spallation products, e.g.,13C,14N,18O,25Mg,26Mg, and 31P. The isotopic ratios 13C/12C,18O/16O,22Ne/20Ne, and (25Mg +26Mg)/24Mg are affected by the Wolf-Rayet star contributions to cosmic rays, while 14N and particularly H and He are affected by the suppression of light nuclei in cosmic rays. The abundance of P is crucial in distinguishing between the two models: (1) stellar flare versus (2) enhanced nonvolatile grain-sputtering material contribution to cosmic rays. The earlier S and T cross sections of 20Ne and 24Mg into 14N and 15N are increased by a factor of 1.5, which reduces the calculated source component of N. The earlier calculated S and T cross sections of Au (and presumably of the Pt to Pb group), into elements with ΔZ < 23 have to be reduced by about 15%, while the even-odd Rudstam parameters are eliminated for the heaviest nuclei. As a result, the calculated secondary components of 61 < Z < 74 are reduced and the calculated primary components are enhanced. This reinforces the need for an enhancement of r-process elements with Z > 60 above the solar system abundances.