Determination of N and O-Atoms, of N₂(A) and N₂(X, v > 13) Metastable Molecules and N₂⁺ Ion Densities in the Afterglows of Ar-N₂ Microwave Discharges

Andre Ricard, Hayat Zerrouki, Jean-Philippe Sarrette

Laplace, Toulouse, France.

DOI: 10.4236/jasmi.2015.54007                

Abstract

Early afterglows of Ar-N₂ flowing microwave discharges are characterized by optical emission spectroscopy. The N and O atoms, the N₂(A) and N₂(X, v > 13) metastable molecules and N₂⁺ ion densities are determined by optical emission spectroscopy after calibration by NO titration for N and O-atoms and measurements of NO and N₂ band intensities. For an Ar-xN₂ gas mixture with × increasing from 2 to 100% at 4 Torr, 100 Watt and an afterglow time of 3 × 10^{- 3} s at the 5 liter reactor inlet, it is found densities in the ranges of (2 - 6) × 10¹⁴ cm^{- 3} for N-atoms, one order of magnitude lower for N₂(X, v > 13) and for O-atoms (coming from air impurity), of 10¹⁰ - 10¹¹ cm^{- 3} for N₂(A) and of 10⁸ - 10⁹ cm^{- 3} for N₂⁺.

Keywords

Ar-N₂ Microwave Discharge, Flowing Afterglow, N-Atoms, N₂ Metastables, N₂⁺ Ions

Conflicts of Interest

The authors declare no conflicts of interest.

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