Modeling MMS Observations at the Earth’s Magnetopause with Hybrid Simulations of Alfvénic Turbulence

FRANCI, LUCALUCAFRANCISTAWARZ, JULIAJULIASTAWARZPAPINI, EMANUELEEMANUELEPAPINIHELLINGER, PETRPETRHELLINGERNAKAMURA, TAKUMATAKUMANAKAMURABURGESS, DAVIDDAVIDBURGESSLandi, SimoneSimoneLandiVERDINI, ANDREAANDREAVERDINIMATTEINI, LORENZOLORENZOMATTEINIERGUN, ROBERTROBERTERGUN2025-03-102025-03-1020200004-637Xhttp://hdl.handle.net/20.500.12386/36591Abstract Magnetospheric Multiscale (MMS) observations of plasma turbulence generated by a Kelvin–Helmholtz (KH) event at the Earth’s magnetopause are compared with a high-resolution two-dimensional (2D) hybrid direct numerical simulation of decaying plasma turbulence driven by large-scale balanced Alfvénic fluctuations. The simulation, set up with four observation-driven physical parameters (ion and electron betas, turbulence strength, and injection scale), exhibits a quantitative agreement on the spectral, intermittency, and cascade-rate properties with in situ observations, despite the different driving mechanisms. Such agreement demonstrates a certain universality of the turbulent cascade from magnetohydrodynamic to sub-ion scales, whose properties are mainly determined by the selected parameters, also indicating that the KH instability-driven turbulence has a quasi-2D nature. The fact that our results are compatible with the validity of the Taylor hypothesis, in the whole range of scales investigated numerically, suggests that the fluctuations at sub-ion scales might have predominantly low frequencies. This would be consistent with a kinetic Alfvén wave-like nature and/or with the presence of quasi-static structures. Finally, the third-order structure function analysis indicates that the cascade rate of the turbulence generated by a KH event at the magnetopause is an order of magnitude larger than in the ambient magnetosheath.STAMPAenModeling MMS Observations at the Earth’s Magnetopause with Hybrid Simulations of Alfvénic TurbulenceArticle10.3847/1538-4357/ab9a472-s2.0-85091748458http://dx.doi.org/10.3847/1538-4357/ab9a47https://iopscience.iop.org/article/10.3847/1538-4357/ab9a47FIS/06 - FISICA PER IL SISTEMA TERRA E IL MEZZO CIRCUMTERRESTREERC sectors::Physical Sciences and Engineering::PE9 Universe sciences: astro-physics/chemistry/biology; solar systems; stellar, galactic and extragalactic astronomy, planetary systems, cosmology, space science, instrumentation