Turbulence at kinetic scales is an unresolved and ubiquitous phenomenon that characterizes both space and laboratory plasmas. Recently, new theories, in situ spacecraft observations and numerical simulations suggest a novel scenario for turbulence, characterized by a so-called phase-space cascade - the formation of fine structures, both in physical and velocity-space. This new concept is here extended by directly taking into account the role of inter-particle collisions, modeled through the nonlinear Landau operator or the simplified Dougherty operator. The characteristic times, associated with inter-particle correlations, are derived in the above cases. The implications of introducing collisions on the phase-space cascade are finally discussed.

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doi.org/10.1088/1361-6587/ab04d5
Plasma Physics and Controlled Fusion
Real-time forecasting of killer electrons on satellite orbits
Centrum Wiskunde & Informatica, Amsterdam (CWI), The Netherlands

Pezzi, O., Valentini, F., Servidio, S., Camporeale, E., & Veltri, P. (P.). (2019). Fourier-Hermite decomposition of the collisional Vlasov-Maxwell system: Implications for the velocity-space cascade. Plasma Physics and Controlled Fusion, 61, 054005:1–054005:14. doi:10.1088/1361-6587/ab04d5