Energy loss of protons with 90 and 100 keV energies penetrating through a hydrogen plasma target has been measured, where the electron density of the plasma is about 1016 cm−3 and the electron temperature is about 1-2 eV. It is found that the energy loss of protons in the plasma is obviously larger than that in cold gas and the experimental results based on the Bethe model calculations can be demonstrated by the variation of effective charge of protons in the hydrogen plasma. The effective charge remains 1 for 100 keV protons, while the value for 90 keV protons decreases to be about 0.92. Moreover, two empirical formulae are employed to extract the effective charge.

中文翻译：

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氢等离子体中 90 和 100 keV 能量的质子电荷状态减速

已经测量了穿过氢等离子体靶的具有 90 和 100 keV 能量的质子的能量损失，其中等离子体的电子密度约为 1016 cm-3，电子温度约为 1-2 eV。发现等离子体中质子的能量损失明显大于冷气体中的能量损失，基于Bethe模型计算的实验结果可以通过氢等离子体中质子有效电荷的变化来证明。100 keV 质子的有效电荷保持为 1，而 90 keV 质子的值减小到约 0.92。此外，采用两个经验公式来提取有效电荷。