Felsenkeller shallow-underground accelerator laboratory for nuclear astrophysics
Felsenkeller shallow-underground accelerator laboratory for nuclear astrophysics
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费尔森凯勒核天体物理浅层地下加速器实验室
DOI：
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发表时间：
2015
期刊：
影响因子：
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通讯作者：
K. Zuber
中科院分区：
文献类型：
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作者：
D. Bemmerer;T. Cowan;S. Gohl;C. Ilgner;A. Junghans;T. Reinhardt;B. Rimarzig;S. Reinicke;M. Röder;K. Schmidt;R. Schwengner;K. Stöckel;T. Szücs;M. Takács;A. Wagner;L. Wagner;K. Zuber
受地下实验室低本底的限制，基于加速器的低本底实验是研究稳定带电粒子核反应的重要手段。这项技术已在意大利Gran Sasso实验室的0.4 MV LUNA加速器上使用多年，并取得了巨大成功，该加速器受到1400 m岩石的保护，免受宇宙射线的影响。然而，氦和碳燃烧的核反应以及天体物理s过程的中子源反应需要比LUNA可用的能量更高的束流能量。此外，太阳聚变反应的研究需要更高能量的新数据。因此，在欧洲目前的NuPECC核物理长期计划中，强烈建议安装一个或多个高能地下加速器。在包括德累斯顿费尔森凯勒地下实验室在内的几个地点的典型核天体物理学装置中，使用相同的HPGe探测器进行了相互比较。发现其45米的岩石覆盖层，加上对剩余μ子通量的积极否决，将背景降低到类似于地下深处场景的水平。在此基础上，研制了一台使用过的5MV、上充电流250 μA、外溅射离子源的串列加速器，并运到德累斯顿。正在高压终端上增加一个射频离子源。该项目现已获得全部资金。预计在不久的将来将在Felsenkeller安装加速器。将报告项目的状况和外部用户计划进入的可能性。
Favored by the low background in underground laboratories, low-background accelerator-based ex- periments are an important tool to study nuclear reactions involving stable charged particles. This technique has been used for many years with great success at the 0.4 MV LUNA accelerator in the Gran Sasso laboratory in Italy, proteced from cosmic rays by 1400 m of rock. However, the nuclear reactions of helium and car- bon burning and the neutron source reactions for the astrophysical s-process require higher beam energies than those available at LUNA. Also the study of solar fusion reactions necessitates new data at higher energies. As a result, in the present NuPECC long range plan for nuclear physics in Europe, the installation of one or more higher-energy underground accelerators is strongly recommended. An intercomparison exercise has been carried out using the same HPGe detector in a typical nuclear astrophysics setup at several sites, including the Dresden Felsenkeller underground laboratory. It was found that its rock overburden of 45 m rock, together with an active veto against the remaining muon flux, reduces the background to a level that is similar to the deep underground scenario. Based on this finding, a used 5 MV pelletron tandem with 250 μA upcharge current and external sputter ion source has been obtained and transported to Dresden. Work on an additional radio-frequency ion source on the high voltage terminal is underway. The project is now fully funded. The installation of the accelerator in the Felsenkeller is expected for the near future. The status of the project and the planned access possibilities for external users will be reported.