Hydrocarbon Collision Cross Sections for Magnetic Fusion: The Methane, Ethane and Propane Families

Abstract

Kinetic analysis of the behaviour of hydrocarbons in fusion plasmas requires knowledge of cross sections for their most relevant collision processes. Upgrades and extensions of the commonly used HYDKIN (HYDride KINetics) online cross section database (based on compilations in 2002) and its data analysis toolbox for collisions of hydrocarbons with electrons and protons in relevant fusion plasma conditions are presented. Newly identified channels for dissociative recombination provide strongly reduced D/XB ratios for Gerö-Band spectroscopy at low temperatures compared to earlier results, in accordance with experimental findings.

Assessment of Hydrocarbon Electron‐Impact Ionization Cross Section Measurements for Magnetic Fusion

“…In addition, cross sections have been generated for processes, for which no experimental data have been available, by making use of well-based (auxiliary) assumptions, like energy invariance of branching ratios (see Sec. 3.4), and certain well established cross section scaling rules [4,5,7]. In 2006 and 2009, respectively, partial electron impact ionization cross section experiments have been carried out at the University of Innsbruck for three types of hydrocarbons, i.e.…”

Uncertainty estimates for theoretical atomic and molecular data

“…These processed, tabulated and fitted data are incorporated into integrated modeling codes, and a key challenge for theory and simulation is the consistent integration of all processes and scales together with a well-founded assessment of uncertainties as they are generated and propagated in the simulations. For the propagation of uncertainties in A+M data through a simple plasma model (no spatial dependence) we note the HydKin toolkit [7], which has been developed to support fusion plasma modeling and other applications.…”

R-matrix calculations of low-energy electron alkane collisions

“…As a result a number of compilations of recommended values for these cross sections have been performed (Morgan 1992, Shirai et al 2002, Kato et al 2009, Reiter and Janev 2010, Fuss et al 2010, Song et al 2014. Individual experimental studies are discussed later in the paper.…”