The Langmuir plasma probe has been widely used in satellites to measure space plasma properties. In one valuable technique, circuits are arranged that measure directly

where I_p = J_pA and A is the probe's area. Use (5.3) to show that

which gives directly the electron temperature T_e. Next show that J_e0 can be calculated from T_e and dl_p/dϕ at a known value of ϕ, according to

The electron density n_e can then be calculated from (5.5).

Equations

Transcribed Image Text:

dIp/do and d² Ip/do2, where Ip = JpA