Operation of cold-cathode magnetron gauges in high magnetic fields

Journal Article · Thu May 01 04:00:00 EDT 1986 · J. Vac. Sci. Technol., A; (United States)

DOI:https://doi.org/10.1116/1.573968· OSTI ID:5521664

Thomas, Jr, S R; Goerz, D A; Pickles, W L

The Mirror Fusion Test Facility (MFTF-B), under construction at LLNL, requires measurement of the neutral gas density in high magnetic fields near the plasma at several axial regions. This background gas pressure (BGP) diagnostic will help us understand the role of background neutrals in particle and power balance, particularly in the maintenance of the cold halo plasma that shields the hot core plasma from the returning neutrals. The BGP consists of several cold-cathode, magnetron-type gauges stripped of their permanent magnets, and utilizes the MFTF-B ambient B-field in strengths of 5--25 kG. Similar gauges have operated in TMX-U in B-fields up to 3 kG. To determine how well the gauges will perform, we assembled a test stand which operated magnetron gauges in an external, uniform magnetic field of up to 30 kG, over a pressure range of 10/sup -8/--10/sup -5/ Torr, at several cathode voltages. This paper describes the test stand and presents the results of the tests.

• Research Organization: Lawrence Livermore National Laboratory, Livermore, California 94550
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 5521664
• Journal Information: J. Vac. Sci. Technol., A; (United States), Journal Name: J. Vac. Sci. Technol., A; (United States) Vol. 4:3; ISSN JVTAD
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700102* -- Fusion Energy-- Plasma Research-- Diagnostics
700209 -- Fusion Power Plant Technology-- Component Development & Materials Testing
DESIGN
ELECTRON TUBES
ELECTRONIC EQUIPMENT
EQUIPMENT
HIGH VACUUM
MAGNETIC MIRRORS
MAGNETRONS
MEASURING INSTRUMENTS
MFTF DEVICES
MICROWAVE EQUIPMENT
MICROWAVE TUBES
OPEN PLASMA DEVICES
OPERATION
PERFORMANCE
PLASMA DIAGNOSTICS
PRESSURE GAGES
PRESSURE MEASUREMENT
TESTING
THERMONUCLEAR DEVICES