天体演化过程中CNO核子辐射俘获反应
C， N， O in Cosmogonic Process
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摘要: C和N核的质子辐射俘获反应对恒星平稳H燃烧阶段的能量产生和元素核合成起重要作用， C， N和O 核的中子辐射俘获是原初核合成和AGB星核合成的关键反应， 精确测定它们天体物理反应率有重要意义。 除13N(p， γ)14O和16N(n， γ)17N等不稳定核的核子辐射俘获反应外， 国际上已完成了其中若干反应的直接测量工作。 但12C(p， γ)13N， 13C(p， γ)14N和15N(p， γ)16O等CNO循环关键反应的实验测量还没有达到天体物理感兴趣的能区。 13C(n， γ)14C，15N(n， γ)16N和18O(n， γ)19O等中子辐射俘获反应测量的能量跨度较大， 截面仍存在较大的不确定性。 介绍了这些反应的研究进展， 并讨论了间接测量这些反应的方法和可行性。 The proton radiative capture reactions of C and N nuclei are important for the energy production and nucleosynthesis in the CNO cycle， and the neutron radiative capture reactions of C， N and O nuclei are key reactions for the inhomogeneous Big Bang nucleosynthesis as well as for the neutron induced CNO cycle in AGB stars. So far， most of these reactions have been measured except some reactions of the unstable nuclei， such as 13N(p， γ)14O and 16N(n， γ)17N. While the direct measured reactions， such as the 12C(p， γ)13N， 13C(p， γ)14N and 15N(p， γ)16O key reactions in CNO cycle， have not reached down to the stellar energies. In addition， the large uncertainties still exist in the measured neutron capture reactions such as 13C(n， γ)14C，15N(n， γ)16N and 18O(n， γ)19O. Thus it is significant to determine their astrophysical reaction rates via the indirect measurements. In this paper， the research status and feasibility of the indirect measurements for these reactions are discussed.Abstract: The proton radiative capture reactions of C and N nuclei are important for the energy production and nucleosynthesis in the CNO cycle， and the neutron radiative capture reactions of C， N and O nuclei are key reactions for the inhomogeneous Big Bang nucleosynthesis as well as for the neutron induced CNO cycle in AGB stars. So far， most of these reactions have been measured except some reactions of the unstable nuclei， such as 13N(p， γ)14O and 16N(n， γ)17N. While the direct measured reactions， such as the 12C(p， γ)13N， 13C(p， γ)14N and 15N(p， γ)16O key reactions in CNO cycle， have not reached down to the stellar energies. In addition， the large uncertainties still exist in the measured neutron capture reactions such as 13C(n， γ)14C，15N(n， γ)16N and 18O(n， γ)19O. Thus it is significant to determine their astrophysical reaction rates via the indirect measurements. In this paper， the research status and feasibility of the indirect measurements for these reactions are discussed.
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