Ion flux maps and helicon source efficiency in the VASIMR VX-100 experiment using a moving Langmuir probe array

This research paper describes the design, setup, and application of a moving multi-Langmuir probe array that measured and mapped ion flux and plasma source efficiency in a flowing plasma with large (∼1.5 T) external magnetic fields in the VASIMR (Variable Specific Impulse Magnetoplasma Rocket) VX-100 experiment. The probe array was swung through an argon plasma revealing a detailed 2-dimensional cross section. Neutral input flow and probe collector bias voltage were scanned from pulse to pulse in an effort to find optimal settings. Secondary electron emission was found to be an important factor that artificially enhanced the measured flux at large negative bias voltages. The most accurate bias voltages were found to be around -20 volts where the flux enhancing effects were minimized. Variations of this probe will be used in more advanced plasma rocket study.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

Masters

Discipline thesis:degree_discipline

Natural Sciences

Grantor

Rice University

Year dc:date.issued

2009

Author dc:creator

• Olsen, Christopher Scott

Advisor dc:contributor.advisor

• Cloutier, Paul A.

• Aerospace engineering
• Plasma physics

Statement dc:rights

• Copyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder.

Language dc:language.iso

eng

Handle dc:identifier.uri

https://hdl.handle.net/1911/61772

OAI identifier oai:identifier

oai:repository.rice.edu:1911/61772