Study on Electron-Impact Excitation and Dielectronic Recombination of Atomic Ions by Crossed Beams Technique

为了发展一种新的技术来研究原子离子的电子碰撞激发和电离过程，我们建立了以下实验装置，测量了几组原子和原子离子的电离截面。在50 cm Seya=纳米冈真空紫外单色仪的入射狭缝上安装了一个对撞室，并在其焦面上安装了一个位置灵敏探测器，从而组装了真空紫外发射光谱仪。我们用新建的光谱仪测量了Ne-2S、Ar-3S、Kr-4S和Xe-5S亚壳层电子的部分电离截面。部分结果已发表在参考文献1、3、4、8和9.2中。为了进行交叉电子束技术，我们研制了一种高效率的紧凑型碱金属和碱土离子源。离子源由炉子、环形喷嘴、金属原子被电离的加热环带和引出电极组成。它提供电流强度为1-10pA的离子束。我们用交叉电子束技术测量了O^+，S^+，S^&lt；2+&gt；(参考文献2)，C^+，N^+，P^+(参考文献5)，F^+，Ne^+，Cl^+，Ar^+(参考文献6)，Ne^&lt；2+&gt；，Ar^&lt；2+&gt；，Kr^&lt；2+&gt；，Xe^&lt；2+&gt；(参考文献7)的单电离截面。此外，我们还测量了Ba2+，Sr2+和Ca2+的双电离截面和三电离截面随入射能量的变化(参考文献4，8)。

With the aim of developing a new technique to study the electron= impact excitation and ionization processes for atomic ions, we have set up the following experimental apparatus and measured several sets of ionization cross sections of atoms and atomic ions.1. We assembled a vacuum ultraviolet (VUV) emission spectrometer by installing a collision chamber on the entrance slit of a 50 cm Seya= Namioka VUV monochromator, and setting a position-sensitive-detector at its focal plane. We determined partial cross sections for ionization of the Ne-2s, Ar-3s, Kr-4s, and Xe-5s subshell electrons, by measuring VUV spectra using the spectrometer newly built. A part of the results has been published in references 1,3,4,8, and 9.2. In the aim to proceed the crossed-electron-ion beams technique, we developed a compact ion source for alkali and alkaline-earth ions of good efficiency. The ion source consists of a furnace, an annular nozzle, a heated Re ribbon where metal atoms are ionized, and an extraction electrode. It supplies an ion beam of 1 to 10 PA current intensity.3. By means of the crossed electron-ion beams technique, we have measured single ionization cross sections of O^+, S^+, S^<2+> (Ref.2), C^+, N^+, P^+ (Ref.5), F^+, Ne^+,Cl^+, Ar^+ (Ref.6), and Ne^<2+>, Ar^<2+>, Kr^<2+>, Xe^<2+> (Ref.7). In addition, we have measured the double and triple ionization cross sections of Ba^+, Sr^+, and Ca^+ as functions of impact energies (Ref.4,8).We are preparing the VUV spectroscopy of atomic ions by the crossed electron-ion beams technique.