First Experiments Aiming for Precise Lamb Shift Measurements on Hydrogen-Like Heavy Ions with Low Temperature Calorimeters
First Experiments Aiming for Precise Lamb Shift Measurements on Hydrogen-Like Heavy Ions with Low Temperature Calorimeters
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首次实验旨在利用低温量热计对类氢重离子进行精确的兰姆位移测量
DOI：
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发表时间：
2008
期刊：
影响因子：
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通讯作者：
M. Trassinelli
中科院分区：
文献类型：
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作者：
V. Andrianov;K. Beckert;P. Beller;A. Bleile;P. Egelhof;A. Gumberidze;S. Ilieva;O. Kiselev;C. Kilbourne;H. Kluge;S. Kraft;D. McCammon;J. Meier;R. Reuschl;Thomas Stöhlker;M. Trassinelli
类氢重离子中兰姆位移的精确测定为非常强的库仑场中的量子电动力学提供了灵敏的测试，这是其他方法无法实现的。为了提高 GSI ESR 存储环中存储的重离子的兰姆位移测量的准确性，开发了一种用于硬 X 射线的量热低温探测器。在第一个实验中应用了由 8 个像素、硅热敏电阻和 Sn 或 Pb 吸收器组成的原型阵列，其中存储的 238U91+ 和 207Pb81+ 离子与内部气体喷射靶相互作用。在这两个实验中，首次使用量热低温探测器在干净、几乎无背景的光谱中清楚地识别出莱曼-α 谱线。在目前的实验条件下，莱曼-α谱线的总探测效率达到了1×10−7，能量分辨率达到了115 eV，与传统的Ge半导体探测器相比，这相当于提高了约半个数量级。最后讨论了数据分析的初步结果和未来的前景。
The precise determination of the Lamb shift in hydrogen-like heavy ions provides a sensitive test of quantum electrodynamics in very strong Coulomb fields, not accessible otherwise. To increase the accuracy of the Lamb shift measurement on stored heavy ions at the ESR storage ring at GSI, a calorimetric low temperature detector for hard X-rays was developed. A prototype array consisting of 8 pixels with silicon thermistors and Sn or Pb absorbers was applied in first experiments with stored 238U91+ and 207Pb81+ ions interacting with an internal gas-jet target. In both experiments the Lyman-α lines were, for the first time by using calorimetric low temperature detectors, clearly identified in clean, almost background-free spectra. A total detection efficiency of 1×10−7 for the Lyman-α lines was reached and an energy resolution of 115 eV was obtained under the present experimental conditions, which corresponds to a considerable improvement of about half an order of magnitude if compared to conventional Ge semiconductor detectors. Finally preliminary results of the data analysis and future perspectives are discussed.