Influence of dissociative recombination on the LTE of argon high-frequency plasmas at atmospheric pressure

Abel Sáinz (1) , Joëlle Margot (2) , Maria Carmen García (1) , Maria Dolores Calzada (1)

1 Grupo de Espectroscopía de Plasmas
2 Groupe de Physique des Plasmas

This work presents a few preliminary results from a collisional-radiative (CR) model intended to describe an argon microwave (2.45 GHz) plasma at atmospheric pressure. This model aims to investigate the influence of dissociative recombination products on the Saha-Boltzmann plasma equilibrium. The model is tested through comparison with experimental results obtained in an argon plasma column generated by a traveling electromagnetic surface-wave, which is suitable to perform a parametric investigation of the plasma. It is shown that dissociative recombination predominantly populates the 4s levels and the ground state. It is further observed that it strongly influences the population of the levels, specially those of lower energy. However, the higher levels (close to the ionization limit) appear to be in equilibrium whatever the plasma density. This allows assuming that the excitation temperature Texc determined from the upper levels in the atomic system in the Boltzmann-plot is equal to Te.

Mots clés: collisional-radiative model; microwave plasma; atmospheric pressure

Domaines: Physique des plasmas [physics.plasm-ph]

Abel Sáinz, Joëlle Margot, Maria Carmen García, Maria Dolores Calzada. Influence of dissociative recombination on the LTE of argon high-frequency plasmas at atmospheric pressure. 2004. ⟨hal-00001854⟩