A tutorial overview on the angular scattering models of Electron-Neutral, Ion-Neutral, Neutral-Neutral, and Coulomb Collisions in Monte Carlo collision modeling on low temperature plasma

Abstract

Over the past decade, massive modeling practices on low temperature plasma (LTP) reveal that input data such as microscopic scattering cross sections are crucial to output macroscopic phenomena. In Monte Carlo collision (MCC) modeling on LTP, angular scattering model is a non-trivial topic in both natural and laboratory plasma. Conforming to the pedagogical purpose of this overview, the classical and quantum theory of binary scattering including the commonly used Born-Bethe approximation is first introduced. State-of-the-art angular scattering models are derived based on the above theories for electron-neutral, ion-neutral, neutral-neutral, and Coulomb collisions. The tutorial is not aiming to provide accurate cross section data by modern approaches in quantum theory, but to introduce analytical angular scattering models from classical, semi-empirical, and first-order perturbation theory. The reviewed models are expected to be readily incorporated into the MCC codes, in which scattering angle is randomly sampled through analytical inversion instead of numerical accept-reject method. Those simplified approaches are very attractive, and demonstrate in many cases the ability to achieve a striking agreement with experiments. Energy partition models on electron-neutral ionization are also discussed with insight from the binary encounter Bethe theory. This overview is written in a tutorial style, in order to serve as a guide for novice in this field, and at the same time as a comprehensive reference for practitioners in MCC modeling on plasma.