7 papers
Secondary drift-driven instabilities in the presence of a parallel-propagating electromagnetic ion cyclotron wave and cold multi-component ions
Opal Issan, Patrick Kilian, Vadim Roytershteyn +2
Electromagnetic ion cyclotron (EMIC) waves are commonly observed in Earth's inner magnetosphere, particularly during geomagnetic storms driven by anisotropic ring-current protons.…
Mixed Hermite-Legendre spectral method for kinetic plasma simulations
Opal Issan, Gian Luca Delzanno, Vadim Roytershteyn
Kinetic collisionless plasma equations are commonly solved via spectral methods in velocity space. The most commonly used spectral method is based on Hermite polynomials with a Max…
Understanding cold electron impact on parallel-propagating whistler chorus waves via moment-based quasilinear theory
Opal Issan, Vadim Roytershteyn, Gian Luca Delzanno +1
Earth's magnetosphere hosts a wide range of collisionless particle populations that interact through various wave-particle processes. Among these, cold electrons, with energies bel…
Conservative projection-based data-driven model order reduction of a fluid-kinetic spectral solver
Opal Issan, Oleksandr Koshkarov, Federico D. Halpern +2
Kinetic simulations are computationally intensive due to six-dimensional phase space discretization. Many kinetic spectral solvers use the asymmetrically weighted Hermite expansion…
Effects of Artificial Collisions, Filtering, and Nonlocal Closure Approaches on Hermite-based Vlasov-Poisson Simulations
Opal Issan, Oleksandr Chapurin, Oleksandr Koshkarov +1
Kinetic simulations of collisionless plasmas are computationally challenging due to phase space mixing and filamentation, resulting in fine-scale velocity structures. This study co…
Conservative Closures of the Vlasov-Poisson Equations Based on Symmetrically Weighted Hermite Spectral Expansion
Opal Issan, Oleksandr Koshkarov, Federico D. Halpern +2
We derive conservative closures of the Vlasov-Poisson equations discretized in velocity via the symmetrically weighted Hermite spectral expansion. The short note analyzes the conse…