An optical emission spectroscopy method for determining the electron temperature and density in low-temperature xenon plasma by using a collisional-radiative model considering the hyperfine structure of emission line into metastable state

A novel state-resolved actinometry method to determine the nitrogen atom number density in the ground state and intra-shell excited states in low-pressure electron cyclotron resonance plasmas

“…The expressions for the rate coefficients can be found in equation ( 2) of table 1. They are calculated according to the cross sections and the assumed EEDF (a Maxwell distribution is taken in this work; see [35]). There are six kinds of reaction kinetics considered in the CR model for the investigation of the key reactions affecting the population of the excited states in tables 3 and 4: (1) electron-impact dissociation processes (R 1 -R 3 ); the total dissociation cross section was measured by Cosby [37], and the branching ratios for R 1 -R 3 are assumed to be 0.5, 0.3, and 0.2, based on the predictions by Zipf et al [38]; (2) electron-impact dissociative excitation processes (R 4 -R 6 ); the cross sections were measured by Filippelli et al [39]; (3) electron-impact excitation processes from the ground and metastable states (R 7 -R 17 ); the cross sections were calculated by Wang et al, using the B-spline R-matrix-with preudostates method [40]; (4) spontaneous radiation (R 18 -R 20 ); their Einstein coefficients are taken from NIST [41]; (5) diffusion processes (R 21 -R 23 ); the diffusion coefficient D n and the sticking coefficient γ can be found in [42][43][44][45].…”

“…Kx,+: loss frequency for the ions u B : Bohm velocity h L : edge-to-center density ratio in axial h R : edge-to-center density ratio in radial electron-impact cross section σ e y→x and the electron energy distribution function (EEDF) g e . A Maxwellian distribution is assumed in the model, as shown in equation ( 4) [35]. The radiation and absorption terms in the rate balance equation are written in equation (5), where the escape factor Γ used is shown in equation (6).…”

Atomic spectrometry update: review of advances in atomic spectrometry and related techniques

“…Wang et al 82 used a collisional radiative and hyperfine splitting model to determine n e and T e in a miniaturised electron-cyclotron-resonance ion thruster along its radial direction. They first determined the metastable density by the self-absorption effect, then used this in rate-balance equations for other excited species.…”