Electronic stopping cross section of tungsten for light ions was experimentally measured in a wide energy interval (20 to 6000 keV for protons and 50 to 9000 keV for helium) in backscattering and transmission geometries. The measurements were carried out in three laboratories (Austria, Germany and Sweden) using five different set-ups, the stopping data deduced from different data sets showed excellent agreement amongst each other, with total uncertainty varying within 1.5–3.8% for protons and 2.2–5.5% for helium, averaged over the respective energy range of each data set. The final data is compared to available data and to widely adopted semi-empirical and theoretical approaches, and found to be in good agreement with most adopted models at energies around and above the stopping maximum. Most importantly, our results extend the energy regime towards lower energies, and are thus of high technological relevance, e.g., in fusion research. At these low energies, our findings also revealed that tungsten – featured with fully and partially occupied f- and d-subshells, respectively – can be modeled as an electron gas for the energy loss process.

在反向散射和透射几何结构中，以宽的能量间隔（质子为20到6000 keV，氦气为50到9000 keV）在宽的能量间隔内实验测量了钨对轻离子的电子截止截面。测量是在三个实验室（奥地利，德国和瑞典）中使用五个不同的设置进行的，从不同数据集推导出的停止数据显示出彼此之间的一致性，质子和2.2的总不确定度在1.5-3.8％之间氦气的–5.5％，在每个数据集各自的能量范围内取平均值。将最终数据与可用数据进行比较，并与广泛采用的半经验和理论方法进行比较，结果发现，在能量大于或等于停止最大值时，该模型与大多数采用的模型都具有良好的一致性。最重要的是，我们的研究结果将能量范围扩展到了较低的能量，因此具有很高的技术适用性，例如在聚变研究中。在这些低能量下，我们的发现还表明，钨（分别具有完全和部分占据的f型和d型子壳）可以被建模为能量损失过程中的电子气。