Plasma and Fusion Research

Volume 3, 019 (2008)

Letters

Modification of Probe Characteristics in a Supersonic Plasma Flow
Sho WATANABE, Haruhiko SAITOH and Zensho YOSHIDA
Department of Advanced Energy, University of Tokyo, Kashiwa 277-8561, Japan
(Received 6 August 2007 / Accepted 25 March 2008 / Published 8 May 2008)

Abstract

The effects of a supersonic plasma flow on emissive Langmuir probes were experimentally investigated using a Pockels electric field sensor. When the flow velocity exceeded the ion sound speed, the probe characteristics were modified, and the emissive probe overestimated the plasma potential. The modification of probe characteristics is explained by the formation of a humped potential profile, caused by a shock in the supersonic plasma flow.

Keywords

flowing plasma, emissive Langmuir probe, Pockels sensor, shock wave, electric field measurement

DOI: 10.1585/pfr.3.019

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This paper may be cited as follows:

Sho WATANABE, Haruhiko SAITOH and Zensho YOSHIDA, Plasma Fusion Res. 3, 019 (2008).