47 citations · 75 across the 11 of their papers we have counts for
12 papers
Analytic non-axisymmetric 3D MHD equilibria without stellarator symmetry
Opal Issan, Jonathan Citrin, Matt Landreman +1
Analytical solutions to the three-dimensional ideal magnetohydrodynamic equilibrium equations and pro…
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…
Anti-symmetric and Positivity Preserving Formulation of a Spectral Method for Vlasov-Poisson Equations
Opal Issan, Oleksandr Koshkarov, Federico D. Halpern +2
We analyze the anti-symmetric properties of a spectral discretization for the one-dimensional Vlasov-Poisson equations. The discretization is based on a spectral expansion in veloc…
Bayesian Inference and Global Sensitivity Analysis for Ambient Solar Wind Prediction
Opal Issan, Pete Riley, Enrico Camporeale +1
The ambient solar wind plays a significant role in propagating interplanetary coronal mass ejections and is an important driver of space weather geomagnetic storms. A computational…
Exact and optimal quadratization of nonlinear finite-dimensional non-autonomous dynamical systems
Andrey Bychkov, Opal Issan, Gleb Pogudin +1
Quadratization of polynomial and nonpolynomial systems of ordinary differential equations is advantageous in a variety of disciplines, such as systems theory, fluid mechanics, chem…
Predicting Solar Wind Streams from the Inner-Heliosphere to Earth via Shifted Operator Inference
Opal Issan, Boris Kramer
Solar wind conditions are predominantly predicted via three-dimensional numerical magnetohydrodynamic (MHD) models. Despite their ability to produce highly accurate predictions, MH…
Deep Learning Enhanced Dynamic Mode Decomposition
Daniel J. Alford-Lago, Christopher W. Curtis, Alexander T. Ihler +1
Koopman operator theory shows how nonlinear dynamical systems can be represented as an infinite-dimensional, linear operator acting on a Hilbert space of observables of the system.…