Scanning optical pyrometer for measuring temperatures in hollow cathodes

Journal Article · Sat Sep 15 00:00:00 EDT 2007 · Review of Scientific Instruments

DOI:https://doi.org/10.1063/1.2774828· OSTI ID:21024276

Polk, J E; Marrese-Reading, C M; Thornber, B; Dang, L; Johnson, L K; Katz, I ^[1]

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1. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States)

Life-limiting processes in hollow cathodes are determined largely by the temperature of the electron emitter. To support cathode life assessment, a noncontact temperature measurement technique which employs a stepper motor-driven fiber optic probe was developed. The probe is driven inside the hollow cathode and collects light radiated by the hot interior surface of the emitter. Ratio pyrometry is used to determine the axial temperature profile. Thermocouples on the orifice plate provide measurements of the external temperature during cathode operation and are used to calibrate the pyrometer system in situ with a small oven enclosing the externally heated cathode. The diagnostic method and initial measurements of the temperature distribution in a hollow cathode are discussed.

• OSTI ID: 21024276
• Journal Information: Review of Scientific Instruments, Vol. 78, Issue 9; Other Information: DOI: 10.1063/1.2774828; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0034-6748
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ELECTRONS
FIBERS
HOLLOW CATHODES
OPERATION
OPTICAL PYROMETERS
ORIFICES
OVENS
PLATES
PROBES
SENSORS
TEMPERATURE DISTRIBUTION
TEMPERATURE MEASUREMENT
THERMOCOUPLES