Self-consistency of electron-THF cross sections using electron swarm techniques

Abstract

The drift velocity and first Townsend ionization coefficient of electrons in gaseous tetrahydrofuran are measured over the range of reduced electric fields 4-1000 Td using a pulsed-Townsend technique. The measured drift velocities and Townsend ionization coefficients are subsequently used, in conjunction with a multi-term Boltzmann equation analysis, as a further discriminative assessment on the accuracy and completeness of a recently proposed set of electron-THF vapor cross sections. In addition, the sensitivity of the transport coefficients to uncertainties in the existing cross sections is presented. As a result of that analysis, a refinement of the momentum transfer cross section for electron-THF scattering is presented, along with modifications to the neutral dissociation and dissociative electron attachment cross sections. With these changes to the cross section database, we find relatively good self-consistency between the measured and simulated drift velocities and Townsend coefficients.

A Relativistic Complex Optical Potential Calculation for Electron–Beryllium Scattering: Recommended Cross Sections

“…One important example of this is in simulating electron transport under an applied external electric field through the background gas of interest (i.e., swarm physics). [26][27][28][29] While we do not explicitly include plots of the available theoretical ICS results for either elastic scattering 7,8 or the summed electronic-states, 7,8,30 it would be remiss of us not to provide a brief summary of their current status.…”

Electron-impact electronic-state excitation of para-benzoquinone

“…37 Our cross sections are then incorporated into transport simulations to describe radiation damage in tissue 38,39 or swarms of electrons that describe physical processes occurring in plasma-like environments. [40][41][42] These computational simulations are important in extending dosimetry to the quantification of induced chemical processes within nanosized volumes and building predictive plasma models that can be used to optimise plasma-based technologies for medical therapies 43,44 or novel chemical processing. [45][46][47][48][49][50] The present investigation continues this rich vein of research, seeking to contribute to the cross section data base 51 that will ultimately be employed to study the behaviour of electrons in pBQbased swarm measurements, similar to what we undertook in Ref.…”

Elastic scattering and vibrational excitation for electron impact on para-benzoquinone

“…[56][57][58][59] Additionally, such databases might also be used in conjunction with Monte Carlo on Boltzmann equation approaches to simulate the transport behaviour of electrons under the influence of an applied electric field on those molecules. [60][61][62][63][64][65] In the latter case, our simulation results are often benchmarked against independent electron swarm experiments that measure transport coefficients such as the drift velocity and Townsend ionisation and diffusion coefficients. 63 In this context, the present investigation on elastic scattering and vibrational excitation seeks to contribute towards building a "correct, absolute, and comprehensive" 66 database, in order to similarly undertake charged-particle track Monte Carlo simulations and Boltzmann equation solution analyses for electron transport in pBQ.…”