Observations of bismuth and lead ionic emission lines excited from grimm-type glow discharge plasmas with pure neon and neon - Argon mixtures

Some of the ionic emission lines for Bi and Pb were investigated with pure Ne and with Ne - Ar glow discharge plasmas. These lines cannot be observed with pure Ar plasmas. However, only small variations in the emission intensities are observed on addition of Ar to a Ne plasma, whereas the emission intensities of the atomic lines for Bi and Pb are enhanced in the presence of Ar. The excitation of these Bi or Pb ionic lines may be attributed to the collisional charge-transfer reactions between Ne ions and Bi or Pb atoms.