TMX heavy ion beam probe
Abstract
A heavy ion beam probe has been used to measure the radial space potential distribution in the central cell of TMX. This was the first beam probe system to utilize computer control, CAMAC instrumentation, and fast time response for broadband fluctuation capabilities. The fast time response was obtained using off-line processing of the energy analyzer detector signals and wideband transimpedance amplifiers. The on-axis space potential was found to be 300-400 V, with phi(sub e)/T(sub ec) approximately equal to 8. The radial potential profile is parabolic when gas box fueling is used. The frequency of observed fluctuations was found to agree with the E x B plasma rotation frequency during the discharge. The measured Tl(sup + +) secondary ion current level is consistent with calculations, given reasonable assumptions for beam attenuation.
- Publication:
-
IEEE Transactions on Plasma Science
- Pub Date:
- August 1994
- DOI:
- 10.1109/27.310639
- Bibcode:
- 1994ITPS...22..341H
- Keywords:
-
- Electrical Measurement;
- Electron Energy;
- Ion Beams;
- Mirror Fusion;
- Plasma Control;
- Plasma Density;
- Plasma Frequencies;
- Plasma Probes;
- Tandem Mirrors;
- Broadband;
- Heavy Ions;
- Ion Currents;
- Rotating Plasmas;
- Plasma Physics