Space-charge limiting current in spherical cathode diodes

• 来源期刊: 中国物理（英文版）
• 关键词: diode space-charge limiting current relativistic electron beam
• 年，卷（期）: 2003,（2）
• 页码范围: 204-207
• 页数: 4页
• 语种: 英文

摘要

The results of the investigation on the space-charge limiting current for a spherical-cathode diode in the nonrelativistic situation are presented in this paper. The results show that the current enhancement factor equals the square of E-field enhancement factor on the cathode surface. The generated space-charge limiting current is deduced.In the case of a pin-shaped-cathode diode, the space-charge limiting current is also obtained, indicating that the current is independent of the geometric parameters of the diode. Analyses of the shielding effects and the conditions for generation of the uniform space-charge limiting beam show that, for pin-arrayed cathodes, the distance between pins should be in the range from 1.2D to 1.5D, where D is the distance between the two electrodes.