固体中氢、氘负离子的形成和电荷交换截面的测量

DETERMINATION OF THE CHARGE EXCHANG CROSS SECTION AND FORMATION OF H- AND D- IN SOLID

用电荷交换的观点,分析在束箔离子相互作用中的负离子形成过程.导出了负离子产额与电荷交换截面的关系为:φ^-=σ_(?)~2/(3σ_i^2).证明φ^-与入射核子速度有关,与停留时间无关.报告了在不同入射速度下,H^+,D^+,H_2^+,D_2^+和H_e^+等种离子在碳膜中产生的H^-,D^-或H_e^-的测量结果.由此得到电子损失截面σ_l和电子浮获截面σ_c的观测值.

Based on the analysis of the atom-solid collision, the formation process of negative ions in the beam-foil interaction by means of the view of the charge exchanging in solids have been analyzed. The relationship between the yield of negative ion and the charge exchanging cross sections and is deduced as: which provids that the depends only on the speed of the bombarding particles and without relation to the dwelltime of the particle in the foil. The measured results of the yields of H, D- or He- produced by the H+, H+, D+ D2+ or H2+ ions with various speeds passing through carbon foil have been reported, separately. The electron loss cross section and electron capture cross section are obtained from the experiments. It is demonstrated that a, is larger than bs and is less than bs. In this paper, the effect of molecular cluster on the charge exchanging process is also discussed.