skip to main content

SciTech ConnectSciTech Connect

Title: Observations of a mode transition in a hydrogen hollow cathode discharge using phase resolved optical emission spectroscopy

Two distinct operational modes are observed in a radio frequency (rf) low pressure hydrogen hollow cathode discharge. The mode transition is characterised by a change in total light emission and differing expansion structures. An intensified CCD camera is used to make phase resolved images of Balmer α emission from the discharge. The low emission mode is consistent with a typical γ discharge, and appears to be driven by secondary electrons ejected from the cathode surface. The bright mode displays characteristics common to an inductive discharge, including increased optical emission, power factor, and temperature of the H{sub 2} gas. The bright mode precipitates the formation of a stationary shock in the expansion, observed as a dark region adjacent to the source-chamber interface.
Authors:
; ; ;  [1] ; ;  [2]
  1. Space Plasma, Power and Propulsion Laboratory, Research School of Physics and Engineering, The Australian National University, Canberra ACT 0200 (Australia)
  2. Department of Physics, York Plasma Institute, University of York, Heslington, York YO10 5DD (United Kingdom)
Publication Date:
OSTI Identifier:
22304480
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 1; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CHARGE-COUPLED DEVICES; ELECTRONS; EMISSION; EMISSION SPECTROSCOPY; EXPANSION; HOLLOW CATHODES; HYDROGEN; INTERFACES; POWER FACTOR; PRECIPITATION; RADIOWAVE RADIATION; SURFACES; VISIBLE RADIATION