Time- and Spectrum-Resolved Study of a Single Cathode Spot in Vacuum

Author

Batrakov, Alexander V. ; Popov, Sergey A. ; Methling, Ralf ; Uhrlandt, Dirk ; Weltmann, Klaus-Dieter

Author_Institution

Inst. of High Current Elec tronics, SB RAS, Tomsk, Russia

Volume

39

Issue

6

fYear

2011

fDate

6/1/2011 12:00:00 AM

Firstpage

1296

Lastpage

1302

Abstract

Optical emission of a single cathode spot is studied to improve understanding of cathode spot initiation and dynamics. A single cathode spot was generated with high reproducibility in a gap under UHV conditions at a liquid Ga-In-alloy cathode. Discharges were initiated by rectangular voltage pulses of 100-ns length produced by a cable generator. Spot radiation was recorded in time with a high temporal and spectral resolution by a spectrograph coupled with a streak camera and a CCD camera. Cathode spot light radiation was found to be weak in the discharge beginning as the equipment set records nothing. Cathode spot radiation becomes bright when cathode spot plasma approaches closely to the anode. Unlike spot initiation in a pure vacuum gap, a cathode spot starts as a bright flash when the gap is filled with plasma.

Keywords

gallium alloys; indium alloys; liquid alloys; plasma diagnostics; time resolved spectra; vacuum arcs; vacuum breakdown; CCD camera; Ga-In; UHV conditions; bright flash; cable generator; cathode spot dynamics; cathode spot initiation; cathode spot light radiation; cathode spot plasma; discharges; liquid Ga-In-alloy cathode; optical emission; pure vacuum gap; rectangular voltage pulses; single cathode spot; spectral resolution; spectrograph; streak camera; temporal resolution; Anodes; Brightness; Cameras; Cathodes; Delay; Discharges; Plasmas; Liquid metal (LM); spectroscopy; trigger circuits; vacuum arcs; vacuum breakdown;

fLanguage

English

Journal_Title

Plasma Science, IEEE Transactions on

Publisher

ieee

ISSN

0093-3813

Type

jour

DOI

10.1109/TPS.2011.2139227

Filename

5759093