Ionization and excitation effects in plasma pencil spectroscopy

Excitation and ionization effect were studied in a radiofrequency plasma pencil.Element lines with lower excitation energies and lower ionization potential are relatively more intensive near the power electrode while the other lines are more intensive near the ground electrode. Observed decreases of some emission lines in presence of another element evidentially depend on the closeness of the excited levels and ionization limits of the involved atoms. The particular emission profile along the discharge axis can be even adopted from an abundant element to a trace element provided that their energy levels are not very different. In case of a bigger energy gap between the interacting atoms the observed effect of the intensity change is weaker and the axial emission profile remains unchanged. Effects of highly concentrated elements solutions on the excitation and rotational temperatures and electron number density were nearly negligible or weak at a constant forwarded power. Also the plasma stability is still excellent regardless of the amount of introduced sample provided that the amount of water is not increased.