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DOE OSTI · 3028472

Collision operator for electron runaway in cold weakly ionised plasmas

Lee, Yeongsun [Seoul National University (Korea, Republic of)] (ORCID:000000034474416X)·Aleynikov, Pavel [Max Planck Institute for Plasma Physics, Greifswald (Germany)] (ORCID:0009000230373679)·de Vries, Peter [ITER Organization, St. Paul Lez Durance (France)]·Park, Jong-Kyu [Seoul National University (Korea, Republic of); Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)] (ORCID:0000000324198667)·Na, Yong-Su [Seoul National University (Korea, Republic of)]
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Abstract

In cold weakly ionised plasmas, the Dreicer generation mechanism can be non-diffusive as demonstrated in a recent study. By expanding the previous letter, we present the detailed description of a proper collision operator to precisely account for the non-diffusive electron kinetics. The operator appropriately combines the Fokker–Planck operator and Boltzmann operator where free-bound collision cross-sections are valid in the low-energy region. The proposed operator is envisaged to predict runaway electron generation in cold weakly ionised plasmas, particularly to design a runaway-free reactor tokamak start-up.

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BibTeXRIS

Lee, Yeongsun [Seoul National University (Korea, Republic of)] (ORCID:000000034474416X), Aleynikov, Pavel [Max Planck Institute for Plasma Physics, Greifswald (Germany)] (ORCID:0009000230373679), de Vries, Peter [ITER Organization, St. Paul Lez Durance (France)], Park, Jong-Kyu [Seoul National University (Korea, Republic of); Princeton Plasma Physics Laboratory (PPPL), Princeton, NJ (United States)] (ORCID:0000000324198667), Na, Yong-Su [Seoul National University (Korea, Republic of)]. 2026-03-23. Collision operator for electron runaway in cold weakly ionised plasmas. https://doi.org/10.1017/s0022377826101329

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