Pressure dependence of the nitrogen atom recombination probability in late afterglows

Abstract

Abstract. Atomic nitrogen recombination probabilities (γ N ) are presented for different materials. They were obtained in late afterglow conditions through a comparison between local measurements of the nitrogen atom density with TALIF (Two-photon Absorption Laser Induced Fluorescence) and atomic concentration profiles calculations at the vicinity of substrates. A comparison is also made between a spatially resolved technique (TALIF) and a non-spatially resolved one (based on optical emission spectroscopy) for the measurement of the N-atom concentration. For each of the studied materials, an inverse pressure dependence of γ N was observed, while the obtained data were found to be in good agreement with previously published values, derived from surface temperature measurements.

Dynamical Monte Carlo methods for plasma-surface reactions

“…To run a particular simulation, the total number of chemisorption sites actually followed in the simulation, [S], has to be defined. The calculation of the fractional coverages (14) from the simulation results is then immediate, from the fractions of simulation sites that are occupied at each instant. The conversation from "simulation particles" or "simulation sites" to real surface and volume densities in equations (17) and 18 Then, for the gas phase concentrations of species…”

Spectroscopic Characteristics of Supersonically Expanding Nitrogen Arc-Jet Plume—Strong Atomic Lines and Weak Molecular Band Spectra

“…where M is the third molecule in the recombination, which is generally an atom of the chamber wall for surface recombination or a gaseous molecule in the plasma for volumetric recombination [16]. The present plasma jet is a plasma plume as a flowing afterglow without power supply with almost sonic velocity, and consequently, the volumetric recombination process should also be considered.…”

“…Now, we consider only first order reaction at the wall [16]. Then, the rate coefficient in (s −1 ) is given by…”

“…2. Then, γ N−wall is estimated to be in the order of 10 −4 [16]. Next, v th is the thermal velocity of N atom perpendicular to the flowing direction, then assumed to be 10 3 m/s if we assume the neutral temperature to be 2000 K. When we observe the plasma jet at z = 25 cm from the nozzle as in Fig.…”

Biological Decontamination Using High and Reduced Pressure Nitrogen Afterglows

“…Indeed by using the data of Ricard et al20, 21 for the N‐atom recombination (total rate k = 6.5 × 10 −33 cm 6 · s −1 ) and of Rouffet et al22 for tube wall losses (destruction probability on the glass tube: γ = 8 × 10 −5 at 5 Torr and γ = 2 × 10 −5 at 20–30 Torr), the total loss of N‐atoms is estimated to be between 27% at 1 slpm and 45% at 0.065 slpm.…”