High energyγ-ray can be used in many fields,such as nuclear resonant fluorescence,nuclear medicine imaging.One of the methods to generate high-energyγ-ray is nuclear resonant reaction.The 19F(p,αγ)16O reaction was...High energyγ-ray can be used in many fields,such as nuclear resonant fluorescence,nuclear medicine imaging.One of the methods to generate high-energyγ-ray is nuclear resonant reaction.The 19F(p,αγ)16O reaction was used to generate 6.13-MeVγ-ray in this work.The angular distribution of 6.13-MeVγ-ray was measured by six LaBr3 detectors.The thick-target yield curve of 6.13-MeVγ-ray had been measured.The maximum yield was determined to be(1.85±0.01)×10^-8γ/proton,which was measured by HPGe detector and LaBr3 detector.The absolute efficiency of all the detectors was calibrated using 60Co and 27Al(p,γ)^28Si reaction at Ep=992 keV.The cross section and total resonant width of the reaction were determined to be 95.1±1.0 mb(1 b=10^-24 cm^2)andΓCM=2.21±0.22 keV,respectively.展开更多
中国锦屏地下实验室(CJPL)坐落于四川省锦屏山中,利用水电站修建的隧道建成。由于其本底环境极低,非常适合开展低本底实验测量。一台基于ECR源的400 k V强流加速器将安装在CJPL中,其可以为核天体物理实验提供流强为12 emA的质子束流,6 ...中国锦屏地下实验室(CJPL)坐落于四川省锦屏山中,利用水电站修建的隧道建成。由于其本底环境极低,非常适合开展低本底实验测量。一台基于ECR源的400 k V强流加速器将安装在CJPL中,其可以为核天体物理实验提供流强为12 emA的质子束流,6 emA的He^+束流和2.5 emA的He^(2+)束流。拟通过非共振反应^(12)C(p,γ)^(13)N以及一系列的共振反应^(27)Al(p,γ)^(28)Si等,对加速器的束流能量进行精确刻度,对束流的能量展宽以及长期稳定性进行测量。由于该加速器正在中国原子能科学研究院进行地面调试,我们利用中国科学院近代物理研究所的320 k V研究平台,进行了^(12)C(p,γ)^(13)N和^(27)Al(p,γ)^(28)Si反应的测试实验。测量结果表明,在质子束流能量为224 keV时,束流的能量展宽约为1.0 keV,束流能量在连续4小时的测量期间,其晃动幅度远小于±200 e V。展开更多
基金Project supported by the National Key Research and Development Program of China(Grant No.2016YFA0400502)the National Natural Science Foundation of China(Grant Nos.11975316 and 11655003)the Continuous Basic Research Project of China(Grant No.WDJC-2019-02).
文摘High energyγ-ray can be used in many fields,such as nuclear resonant fluorescence,nuclear medicine imaging.One of the methods to generate high-energyγ-ray is nuclear resonant reaction.The 19F(p,αγ)16O reaction was used to generate 6.13-MeVγ-ray in this work.The angular distribution of 6.13-MeVγ-ray was measured by six LaBr3 detectors.The thick-target yield curve of 6.13-MeVγ-ray had been measured.The maximum yield was determined to be(1.85±0.01)×10^-8γ/proton,which was measured by HPGe detector and LaBr3 detector.The absolute efficiency of all the detectors was calibrated using 60Co and 27Al(p,γ)^28Si reaction at Ep=992 keV.The cross section and total resonant width of the reaction were determined to be 95.1±1.0 mb(1 b=10^-24 cm^2)andΓCM=2.21±0.22 keV,respectively.
基金National Natural Science Foundation of China(11405096,11490564,11775133)National Undergraduate Innovation and Entrepreneurship Training Program of Shandong University at Weihai of China~~
文摘中国锦屏地下实验室(CJPL)坐落于四川省锦屏山中,利用水电站修建的隧道建成。由于其本底环境极低,非常适合开展低本底实验测量。一台基于ECR源的400 k V强流加速器将安装在CJPL中,其可以为核天体物理实验提供流强为12 emA的质子束流,6 emA的He^+束流和2.5 emA的He^(2+)束流。拟通过非共振反应^(12)C(p,γ)^(13)N以及一系列的共振反应^(27)Al(p,γ)^(28)Si等,对加速器的束流能量进行精确刻度,对束流的能量展宽以及长期稳定性进行测量。由于该加速器正在中国原子能科学研究院进行地面调试,我们利用中国科学院近代物理研究所的320 k V研究平台,进行了^(12)C(p,γ)^(13)N和^(27)Al(p,γ)^(28)Si反应的测试实验。测量结果表明,在质子束流能量为224 keV时,束流的能量展宽约为1.0 keV,束流能量在连续4小时的测量期间,其晃动幅度远小于±200 e V。
文摘慢速中子俘获过程(s过程)是合成比铁重元素的重要途径之一。^(22)Ne(α, n)^(25)Mg反应是大质量AGB星中s过程主要的中子源,其中的^(22)Ne主要通过14N(α,γ)18F(β+)18O(α,γ)^(22)Ne反应链合成。该反应链中关键反应18O(α,γ)^(22)Ne在天体物理感兴趣能区的截面非常低,其天体反应率主要来自于^(22)Neα分离阈附近低能共振态的贡献,但目前相关能级的共振参数严重缺失。在HI-13串列加速器的Q3D磁谱仪上,通过测量18O(6Li, d)^(22)Ne反应的角分布,利用DWBA分析确定了^(22)Ne分离阈附近共振能级Eα=470 ke V的自旋宇称为0+,为后续计算18O(α,γ)^(22)Ne的天体反应率打下了基础。
基金supported by the National Natural Science Foundation of China(1149056312125509U18672111196114100311775133and 12175152)the Continuous Basic Scientific Research Project No.WDJC-2019-13+1 种基金the Equipment Research and Development Project of Chinese Academy of Sciences(28Y531040)research fund of CNNC。
