Modelling of relativistic electron transport with non-relativistic DKES solver

The paper considers the electron transport in toroidal systems taking into account relativistic effects for electrons. The treatment is based on the relativistic drift-kinetic equation with the thermodynamic equilibrium given by the relativistic Maxwell-JÜttner distribution function. The definition of relativistic fluxes is given in a classic-like form using the same set of thermodynamic forces as in the classical (non-relativistic) approach. Such a formulation allows us to apply the currently used non-relativistic solvers for calculation of relativistic mono-energetic transport coefficients. As an example, the procedure for calculating electron fluxes is proposed, in which relativistic effects are taken into account using the DKES code. The model can be easily implemented in various transport codes, developed for the non-relativistic limit, making them accurate also for hot plasmas with non-negligible relativistic effects. © 2024 The Author(s).