Electron and Proton Energy Loss via Rovibrational Excitation of Molecular Hydrogen in Fusion Detached Plasmas

Abstract

Electron and proton energy-loss rate coefficients in a fusion detached plasma, formed through collisions with molecular hydrogen, are investigated using a rovibrationally resolved collisional-radiative model of molecular hydrogen [K. Sawada and M. Goto, Atoms 4, 29 (2016)]. The rovibrational population distribution of X¹Σ_g⁺ in electrons and protons, both with a temperature of 1 eV and density of 10¹⁶ cm⁻³, is solved time-dependently with an initial 300 K Boltzmann distribution. Energy loss of electrons by rovibrational excitation in X¹Σ_g⁺ is approximately one or two orders of magnitude larger than that by excitation to the triplet b³Σ_u⁺ state.