Operating Characteristics of Cylindrical and Annular Helicon Sources (Preprint)
Abstract
The power required to create an ionized plasma is a significant energy loss mechanism in typical electric propulsion systems. The use of wave-driven helicon sources is one approach that has been considered as a means of reducing this loss due to the reportedly low ionization cost found in these devices. In order to extend the benefits of the helicon ionization mechanism to the widest possible array of devices, a program has been initiated to develop and demonstrate a helicon operating in an annular configuration. A 15-cm diameter helicon source has been operated on both argon and xenon gas at power levels ranging from 200 W to 3.2 kW and magnetic field strengths up to 1.6 kG for both cylindrical and annular configurations. Measurements of the resultant plasma load impedance have revealed distinct transitions to a high-resistance, visually bright regime associated with operation in the helicon mode. The qualitative similarity of the load response for both geometric configurations supports the notion that helicon sources can be created in both cylindrical and annular modes.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 22, 2007
- Accession Number
- ADA473588
Entities
People
- Brian E. Beal
- Fabian Mak
Organizations
- Air Force Research Laboratory