【摘 要】
：
The 25Mg(p,γ)26Al reaction plays an important role in the study of cosmic 1.809 MeV γ-ray as a signature of ongoing nucleosynthesis in the Galaxy.At astrophysical temperature around 0.1 GK,the 25Mg(p,γ)26Al reaction rates are dominated by the 92 keV reson
【机 构】
：
China Institute of Atomic Energy,P.O.Box 275 10 ,Beijing 102413,China;Key Laboratory of Beam Technol
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The 25Mg(p,γ)26Al reaction plays an important role in the study of cosmic 1.809 MeV γ-ray as a signature of ongoing nucleosynthesis in the Galaxy.At astrophysical temperature around 0.1 GK,the 25Mg(p,γ)26Al reaction rates are dominated by the 92 keV resonance capture process.We report a precise measurement of the 92 keV 25Mg(p,γ)26Al resonance in the day-one experiment at Jinping Underground Nuclear Astrophysics experiment (JUNA) facility in the China Jinping Underground Laboratory (CJPL).The reso-nance strength and ground state feeding factor are determined to be 3.8±0.3 ×10-10 eV and 0.66 ± 0.04,respectively.The results are in agreement with those reported in the previous direct under-ground measurement within uncertainty,but with significantly reduced uncertainties.Consequently,we recommend new 25Mg(p,γ)26Al reaction rates which are by a factor of 2.4 larger than those adopted in REACLIB database at the temperature around 0.1 GK.The new results indicate higher production rates of 26gAl and the cosmic 1.809 MeV γ-ray.The implication of the new rates for the understanding of other astrophysical situations is also discussed.
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