Measurement of the ^{18}O(α, γ)^{22}Ne Reaction Rate at JUNA and Its Impact on Probing the Origin of SiC Grains.
Measurement of the ^{18}O(α, γ)^{22}Ne Reaction Rate at JUNA and Its Impact on Probing the Origin of SiC Grains.
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JUNA ^{18}O(α, γ)^{22}Ne 反应速率的测量及其对探测 SiC 晶粒起源的影响。
DOI：
10.1103/physrevlett.130.092701
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发表时间：
2023
影响因子：
8.6
通讯作者：
W. Liu
中科院分区：
文献类型：
--
作者：
L. H. Wang;J. Su;Y. P. Shen;J. He;M. Lugaro;B. Szanyi;A. Karakas;L. Zhang;X. Li;B. Guo;G. Lian;Z. H. Li;Y. B. Wang;L. Chen;B. Cui;X. D. Tang;B. Gao;Q. Wu;L. Sun;S. Wang;Y. Sheng;Y. J. Chen;H. Zhang;Z. Li;L. Song;X. Jiang;W. Nan;W. Nan;L. Zhang;F. Cao;T. Jiao;L. H. Ru;Jia Hua Cheng;M. Wiescher;W. Liu
The ^{18}O(α,γ)^{22}Ne reaction is critical for AGB star nucleosynthesis due to its connection to the abundances of several key isotopes, such as ^{21}Ne and ^{22}Ne. However, the ambiguous resonance energy and spin-parity of the dominant 470 keV resonance leads to substantial uncertainty in the ^{18}O(α,γ)^{22}Ne reaction rate for the temperature of interest. We have measured the resonance energies and strengths of the low-energy resonances in ^{18}O(α,γ)^{22}Ne at the Jinping Underground Nuclear Astrophysics experimental facility (JUNA) with improved precision. The key 470 keV resonance energy has been measured to be E_{α}=474.0±1.1 keV, with such high precision achieved for the first time. The spin-parity of this resonance state is determined to be 1^{-}, removing discrepancies in the resonance strengths in earlier studies. The results significantly improve the precision of the ^{18}O(α,γ)^{22}Ne reaction rates by up to about 10 times compared with the previous data at typical AGB temperatures of 0.1-0.3 GK. We demonstrate that such improvement leads to precise ^{21}Ne abundance predictions, with an impact on probing the origin of meteoritic stardust SiC grains from AGB stars.
The ^{18}O(α,γ)^{22}Ne reaction is critical for AGB star nucleosynthesis due to its connection to the abundances of several key isotopes, such as ^{21}Ne and ^{22}Ne. However, the ambiguous resonance energy and spin-parity of the dominant 470 keV resonance leads to substantial uncertainty in the ^{18}O(α,γ)^{22}Ne reaction rate for the temperature of interest. We have measured the resonance energies and strengths of the low-energy resonances in ^{18}O(α,γ)^{22}Ne at the Jinping Underground Nuclear Astrophysics experimental facility (JUNA) with improved precision. The key 470 keV resonance energy has been measured to be E_{α}=474.0±1.1 keV, with such high precision achieved for the first time. The spin-parity of this resonance state is determined to be 1^{-}, removing discrepancies in the resonance strengths in earlier studies. The results significantly improve the precision of the ^{18}O(α,γ)^{22}Ne reaction rates by up to about 10 times compared with the previous data at typical AGB temperatures of 0.1-0.3 GK. We demonstrate that such improvement leads to precise ^{21}Ne abundance predictions, with an impact on probing the origin of meteoritic stardust SiC grains from AGB stars.