High-resolution imaging of vacuum arc cathode spots

Journal Article · Thu Feb 01 00:00:00 EST 1996 · IEEE Transactions on Plasma Science

DOI:https://doi.org/10.1109/27.491695· OSTI ID:244924

Anders, A; Anders, S ^[1]; Juettner, B ^[2]; Lueck, H ^[3]

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1. Lawrence Berkeley National Lab., CA (United States)
2. Max-Planck-Institut fuer Plasmaphysik, Berlin (Germany)
3. Universitaet Hannover (Germany). Institut fuer Plasmaphysik

Imaging differential laser absorption spectroscopy was used to map the electron density distribution of vacuum arc cathode spots. The temporal resolution was determined by the sequence of laser pulses (pulses of 0.4-ns duration, with 3-ns separation). The spatial resolution was limited by diffraction (better than 5 {micro}m). Fragments of cathode spots have been detected, and the following parameters could be derived: current density on the order of 10{sup 12} A/m{sup 2}, plasma density greater than 3--6 {times} 10{sup 26} m{sup {minus}3}, fragment size 5--10 {micro}m and smaller, current per fragment 20--40 A (for copper electrodes and arc current 50--150 A), and the lifetime of dense plasma on the order of a few nanoseconds.

• DOE Contract Number: AC03-76SF00098
• OSTI ID: 244924
• Journal Information: IEEE Transactions on Plasma Science, Vol. 24, Issue 1; Other Information: PBD: Feb 1996
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ELECTRIC ARCS
ELECTRON DENSITY
PLASMA DIAGNOSTICS
LASER SPECTROSCOPY
ABSORPTION SPECTROSCOPY
IMAGES
CURRENT DENSITY
PLASMA DENSITY
TIME RESOLUTION