Secondary Electron Emission from Dielectric Materials of a Hall Thruster with Segmented Electrodes

Dunaevsky, A. ; Raitses, Y. ; Fisch, N.J.

Princeton University. Plasma Physics Laboratory.

关键词: 70 Plasma Physics And Fusion Technology;    Dielectric Materials;    Electrodes;    36 Materials Science;    Backscattering;   

DOI  :  10.2172/812024
RP-ID  :  PPPL-3787
RP-ID  :  AC02-76CH03073
RP-ID  :  812024

美国|英语

来源: UNT Digital Library

【 摘 要 】

The discharge parameters in Hall thrusters depend strongly on the yield of secondary electron emission from channel walls. Comparative measurements of the yield of secondary electron emission at low energies of primary electrons were performed for several dielectric materials used in Hall thrusters with segmented electrodes. The measurements showed that at low energies of primary electrons the actual energetic dependencies of the total yield of secondary electron emission could differ from fits, which are usually used in theoretical models. The observed differences might be caused by electron backscattering, which is dominant at lower energies and depends strongly on surface properties. Fits based on power or linear laws are relevant at higher energies of primary electrons, where the bulk material properties play a decisive role.