The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.
an arc discharge with artificial cathode heating; the arc burns stably at low voltages between the electrodes—for example, in potassium and sodium vapors, as low as 0.5 volt. (SeeARC DISCHARGE: Non-self-sustaining arc discharge.)
The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.