Ring-averaged ion velocity distribution function probe for laboratory magnetized plasma experiment

Eiichirou Kawamori, Jinting Chen, Chiahsuan Lin, Zongmau Lee

Research output: Contribution to journalArticlepeer-review


Ring-averaged velocity distribution function of ions at a fixed guiding center position is a fundamental quantity in the gyrokinetic plasma physics. We have developed a diagnostic tool for the ring averaged velocity distribution function of ions for laboratory plasma experiments, which is named as the ring-averaged ion distribution function probe (RIDFP). The RIDFP is a set of ion collectors for different velocities. It is designed to be immersed in magnetized plasmas and achieves momentum selection of incoming ions by the selection of the ion Larmor radii. To nullify the influence of the sheath potential surrounding the RIDFP on the orbits of the incoming ions, the electrostatic potential of the RIDFP body is automatically adjusted to coincide with the space potential of the target plasma with the use of an emissive probe and a voltage follower. The developed RIDFP successfully measured the equilibrium ring-averaged velocity distribution function of a laboratory magnetized plasma, which was in accordance with the Maxwellian distribution having an ion temperature of 0.2 eV.

Original languageEnglish
Article number103507
JournalReview of Scientific Instruments
Issue number10
Publication statusPublished - 2017 Oct 1

All Science Journal Classification (ASJC) codes

  • Instrumentation


Dive into the research topics of 'Ring-averaged ion velocity distribution function probe for laboratory magnetized plasma experiment'. Together they form a unique fingerprint.

Cite this