We study the electron-impact induced ionization of O₂ from threshold to 120 eV using the electron spectroscopy method. Our approach is simple in concept and embodies the ion source with a collision chamber and a mass spectrometer with a quadruple filter as a selector for the product ions. The combination of these two devices makes it possible to unequivocally collect all energetic fragment ions formed in ionization and dissociative processes and to detect them with known efficiency. The ion source allows varying and tuning the electron-impact ionization energy and the target-gas pressure. We demonstrate that for obtaining reliable results of cross-sections for inelastic processes and determining mechanisms for the formation of O+(4S,2D,2P) ions, it is crucial to control the electron-impact energy for production of ion and the pressure in the ion source. A comparison of our results with other experimental and theoretical data shows good agreement and proves the validity of our approach.

中文翻译：

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从阈值到 120 eV 能量范围的 O2 的电子碰撞电离和离子碎裂

_{我们使用电子能谱法研究了 O 2}从阈值到 120 eV 的电子碰撞诱导电离。我们的方法概念简单，离子源带有碰撞室，质谱仪带有四重过滤器作为产物离子的选择器。这两种设备的结合可以明确地收集在电离和解离过程中形成的所有高能碎片离子，并以已知的效率检测它们。离子源允许改变和调整电子撞击电离能量和目标气体压力。我们证明，为了获得非弹性过程的横截面的可靠结果并确定 O 的形成机制+(4小号,2D,2磷)离子，控制用于产生离子的电子撞击能量和离子源中的压力是至关重要的。我们的结果与其他实验和理论数据的比较显示出良好的一致性，并证明了我们方法的有效性。