Theoretical Study of Spherical Langmuir Probe in Maxwellian Plasma

The Langmuir Probe is the key plasma diagnostic used by scientists interested in plasma characterization to measure the internal parameters of the bulk of the plasma. Spherical Langmuir Probes have been installed on satellites and sounding rockets to observe the general characteristics of thermal plasma in the ionosphere for more than five decades. Because of its simplicity and convenience, the Langmuir probe is one of the most frequently installed scientific instruments on spacecraft. This research explores the theoretical study of Spherical Langmuir Probe I-V Characteristics. With the help of the (volt-ampere curves) of spherical Langmuir probes, the different parameters of plasma can be determined such as plasma potential, floating potential, probe currents in different probe voltage and so on. The effect of electron temperature on the Electron Energy Distribution Function (EEDF) was also analyzed. At higher energy range, the shape of the distribution recovers and the tail trend with energy is maintained and decreases exponentially.