Electric field measurement in microwave discharge ion thruster with electro-optic probe
- The University of Tokyo, Bunkyo-ku, Tokyo 113-8656 (Japan)
- Microsystem Integration Laboratories, Nippon Telegraph and Telephone, Morinosato, Atsugi-shi, Kanagawa 243-0198 (Japan)
- Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Chuo-ku, Sagamihara, Kanagawa 229-8510 (Japan)
In order to understand the internal phenomena in a microwave discharge ion thruster, it is important to measure the distribution of the microwave electric field inside the discharge chamber, which is directly related to the plasma production. In this study, we proposed a novel method of measuring a microwave electric field with an electro-optic (EO) probe based on the Pockels effect. The probe, including a cooling system, contains no metal and can be accessed in the discharge chamber with less disruption to the microwave distribution. This method enables measurement of the electric field profile under ion beam acceleration. We first verified the measurement with the EO probe by a comparison with a finite-difference time domain numerical simulation of the microwave electric field in atmosphere. Second, we showed that the deviations of the reflected microwave power and the beam current were less than 8% due to inserting the EO probe into the ion thruster under ion beam acceleration. Finally, we successfully demonstrated the measurement of the electric-field profile in the ion thruster under ion beam acceleration. These measurements show that the electric field distribution in the thruster dramatically changes in the ion thruster under ion beam acceleration as the propellant mass flow rate increases. These results indicate that this new method using an EO probe can provide a useful guide for improving the propulsion of microwave discharge ion thrusters.
- OSTI ID:
- 22094039
- Journal Information:
- Review of Scientific Instruments, Vol. 83, Issue 12; Other Information: (c) 2012 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
- Country of Publication:
- United States
- Language:
- English
Similar Records
Internal plasma potential measurements of a Hall thruster using xenon and krypton propellant
A high sensitivity momentum flux measuring instrument for plasma thruster exhausts and diffusive plasmas
Related Subjects
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
ACCELERATION
ATMOSPHERES
BEAM CURRENTS
COMPUTERIZED SIMULATION
COOLING SYSTEMS
DISTRIBUTION
ELECTRIC FIELDS
FLOW RATE
HIGH-FREQUENCY DISCHARGES
ION BEAMS
ION THRUSTERS
METALS
MICROWAVE RADIATION
PLASMA
PLASMA PRODUCTION