ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
The current collected by a finite-length cylindrical probe is calculated numerically from a self-consistent solution to the Poisson–Vlasov system of equations. A Boltzmann distribution is assumed for the electrons, and results are compared to the standard "orbital-motion-limited'' theory. When the probe is very long compared to the sheath thickness and the ratio of probe radius to electron Debye length, Rp/λDe (approximately-less-than) 1, the collected current agrees with the orbital-motion theory for cylindrical probes; when the probe is very short compared to the sheath thickness and Rp/λDe (approximately-less-than) 1, the collected current agrees with the orbital-motion theory for spherical probes. When the probe length is comparable to the sheath thickness, there is a critical potential above which the probe behaves as a sphere and below which it behaves as a cylinder. Ion charge density, space potential, and ion particle orbits are displayed graphically in the sheath plasma surrounding the probe tip.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.347629
