Electron collision cross section set for N₂ and electron transport in N₂, N₂/He, and N₂/Ar

Abstract

Electron collision cross section set for N2 is proposed. The proposed set consists of vibrational elastic momentum transfer cross section and cross sections for 31 rotational excitation, 29 rotational deexcitation, 10 vibrational excitation, 17 electronic excitation, 2 neutral dissociation, and 5 ionization collision processes. Electron transport coefficients in N2, N2/He, and N2/Ar are calculated by Monte Carlo method with considering anisotropic inelastic electron scattering and partitioning of the residual energy after the ionization collision on the basis of experimental results. The reliability of the proposed electron collision cross section set is demonstrated by comparing the calculated and measured electron transport coefficients in a wide range of reduced electric fields, E/N (E: electric field strength, N: number density of gas molecules). Comparison of the values of the electron transport coefficients in N2 calculated from eight individual cross section sets partly provided on LXCat with the measured values is also carried out. Furthermore, the effect of anisotropic inelastic electron scattering on the electron transport coefficients is examined. The electron transport coefficients in N2 are found to be affected by considering anisotropic electron scattering with increasing E/N values, and the longitudinal third-order transport coefficient is found to be sensitive to considering anisotropic electron scattering even at middle E/N values.

Coupling plasma physics and chemistry in the PIC model of electric propulsion: Application to an air-breathing, low-power Hall thruster

“…Detailed overviews of the relevant cross-sections with nitrogen species are given in Brunger and Buckman [33], Itikawa [34], Tabata et al [35,36], Thorsteinsson and Gudmundsson [30], and Kawaguchi et al [37]. The complete reaction set used in the present model is reported in Table 2.…”

Third-order transport coefficients for electrons in N2 and CF4: effects of non-conservative collisions, concurrence with diffusion coefficients and contribution to the spatial profile of the swarm

“…They have subsequently measured the longitudinal component of the third-order transport tensor for electrons in N 2 by employing the arrival time spectra experiment. Kawaguchi et al have further verified these results by using Monte Carlo simulations [58,62].…”

“…L and those of Kawaguchi and co-workers for n 2 0 D 3L is a clear indication of different sets of cross sections used as input data in Monte Carlo simulations. The sensitivity of the third-order transport coefficients to the cross sections used in the transport calculations was demonstrated by Kawaguchi and coworkers [62]. The deviation of n 2 0 D α 3 3L from n 2 0 D 3L for higher values of E/n 0 can be attributed to neglecting alpha parameters of fourth and higher order in equation from which the values of n 2 0 D α 3 3L are determined, as discussed by Kawaguchi et al [58].…”

Simulating the Upper Hybrid Instability as a Cause for 150 km Echoes

“…If an inelastic collision occurs, the electron kinetic energy is reduced by the collision energy to simulate excitation of an N 2 molecule, before being scattered in the same way. Electron‐Nitrogen collisions have 25 relevant collision types (effective momentum transfer, 1 rotational excitation, 9 vibrational excitations, 12 electronic excitations, 1 neutral dissociation, and 1 ionization cross section) (Itikawa, 2006; Kawaguchi et al., 2021), however in the energy range we examine, W < 12 eV with the majority having W < 0.1 eV, we can to first order ignore ionization and electronic excitations. To simulate 150 km echoes, we have chosen to implement the elastic and first vibrational ( V = 0 → 1) cross sections from the Morgan Database at LxCat (Morgan, N.D.).…”