Development of a theory to describe constricted positive columns in alkali-metal-seeded rare gases

It is shown that four equations (covering respectively the electron energy balance, ion balance, current continuity and energy balance) are necessary and sufficient to describe the constricted positive columns of certain arc discharges in alkali-metal-seeded rare gases. The internal mechanisms and basic structural features of one such column are discussed in terms of the theory, which is shown to give a satisfactory explanation of the column properties.