Abstract
The “virtual cathode” structure formed by the space charge near a thermionic emission cathode has a great influence on the characteristics of the emissive probe. The relationship between the characteristics of the virtual cathode in a vacuum and the probe filament temperature is not clear. Considering the initial velocity of the thermal electrons, we have derived an analytical expression of the virtual cathode potential. Combined with the experimental data, the dependence of the virtual cathode characteristics on the filament temperature of the emissive probe is obtained. The results show that the depth and the space scale of the virtual cathode increase almost linearly with the increase of the filament temperature. Additionally, a 1-D electrostatic particle-in-cell code is used to simulate the temporal evolution of the virtual cathode in a vacuum. The numerical simulation results are in good agreement with the theoretical calculation results.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
