Effects of DC Preionization Voltage and Radial Location on Pulsed Inductive Plasma Formation

Ryan A. Pahl, Joshua L. Rovey

Research output: Contribution to journalArticlepeer-review


The effects of dc preionization (PI) voltage and radial location on plasma formation repeatability are presented for argon prefills of 20-200 mtorr with a discharge energy of 79.5 J at 15 kV. Current profiles of a ringing theta-pinch are compared with circuit simulation in SPICE to estimate plasma resistance and inductance and quantify plasma formation uncertainty. Plasma thickness is calculated using axial imaging and experimental geometry and used to determine the mutual inductance coupling of the plasma and the theta-pinch coil. At all pressures tested, plasma formation failed to occur in the absence of dc PI. At pressures less than 100 mtorr, PI voltage has a significant impact on plasma formation, repeatability, and energy coupling into the plasma. At 20 mtorr, 0.20 W of dc power is sufficient to stabilize plasma formation at the first zero-crossing of the current. With 1.5 W, an additional 39% of inductive energy is coupled into the plasma. Increasing pressure also increased plasma repeatability and resulted in a convergence of plasma circuit parameters.

Original languageEnglish (US)
Article number7299667
Pages (from-to)3883-3888
Number of pages6
JournalIEEE Transactions on Plasma Science
Issue number11
StatePublished - Nov 1 2015
Externally publishedYes


  • Argon
  • plasma inductance
  • plasma resistance
  • preionization (PI)
  • pulsed inductive plasma (PIP)

ASJC Scopus subject areas

  • Nuclear and High Energy Physics
  • Condensed Matter Physics


Dive into the research topics of 'Effects of DC Preionization Voltage and Radial Location on Pulsed Inductive Plasma Formation'. Together they form a unique fingerprint.

Cite this