A high-efficiency gas target setup for underground experiments, and redetermination of the branching ratio of the 189.5 keV 22Ne(p, $\gamma$ ? )23Na resonance
A high-efficiency gas target setup for underground experiments, and redetermination of the branching ratio of the 189.5 keV 22Ne(p, $\gamma$ ? )23Na resonance
复制标题
用于地下实验的高效气体靶装置，并重新确定189.5 keV 22Ne(p, $gamma$ ? )23Na 共振的分支比
DOI：
10.1140/epja/i2018-12476-7
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发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Ferraro F
中科院分区：
文献类型：
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作者：
Ferraro F
低背景、高光度的装置极大地促进了天体物理学感兴趣的核反应的实验研究。地下核天体物理实验室（LUNA）400 kV加速器位于意大利格兰萨索国家实验室（INFN-LNGS）的地下深处，可提供超低宇宙线感应本底和高强度（250-500μA）的质子和离子束。为了充分利用这些功能，高纯度，同位素富集气体的再循环气体靶系统耦合到一个高效率，六倍光学分段锗酸铋（BGO）射线检测器。束流强度的测量采用具有恒定温度梯度的束流量热计。压力和温度的测量已经进行了几个位置沿着的光束路径，并得到的气体密度分布已被确定。校准的强度标准和众所周知的keV 14 N（p，）15 O共振被用来确定射线检测效率，并验证模拟的目标和检测器设置。作为一个例子，我们对最近测量的~（22）Ne（p，）~（23）Na反应中keV处的共振进行了高统计性的研究，并确定了共振的衰变分支比。
The experimental study of nuclear reactions of astrophysical interest is greatly facilitated by a low-background, high-luminosity setup. The Laboratory for Underground Nuclear Astrophysics (LUNA) 400kV accelerator offers ultra-low cosmic-ray induced background due to its location deep underground in the Gran Sasso National Laboratory (INFN-LNGS), Italy, and high intensity, 250-500μA, proton andion beams. In order to fully exploit these features, a high-purity, recirculating gas target system for isotopically enriched gases is coupled to a high-efficiency, six-fold optically segmented bismuth germanate (BGO)-ray detector. The beam intensity is measured with a beam calorimeter with constant temperature gradient. Pressure and temperature measurements have been carried out at several positions along the beam path, and the resultant gas density profile has been determined. Calibrated-intensity standards and the well-knownkeV14N(p,)15O resonance were used to determine the-ray detection efficiency and to validate the simulation of the target and detector setup. As an example, the recently measured resonance atkeV in the22Ne(p,)23Na reaction has been investigated with high statistics, and the-decay branching ratios of the resonance have been determined.