arXiv subjects

Young Dae Yoon

Publications and source records attributed to Young Dae Yoon.

3 recordsLinked to original sources

arXiv2026

Firewall effect on electron acceleration by R-waves and parallel electric fields

We report an unanticipated electron dynamics in a classical setting of a uniform magnetic field, a parallel electric field, and a right-handed circularly polarized wave (R-wave). The setting admits a natural trajectory that a particle accelerated by the electric field reaches a Doppler-shifted cyclotron resonance and becomes trapped in the resonance space. Remarkably, once it becomes resonantly trapped, the electron undergoes reversal of parallel acceleration together with perpendicular energization, despite the parallel electric field remaining constant. This counterintuitive behavior has important implications for particle scattering in various laboratory and space plasmas. Applied to fusion devices, particle-in-cell simulations show that an externally injected R-wave can act as a firewall suppressing further runaway-electron acceleration.

physics.plasm-ph↗

arXiv2026

Canonical Vorticity Perspective on Magnetogenesis: Unifying Weibel, Biermann, and Beyond

We briefly review the current status of magnetogenesis, a cross-disciplinary field that bridges cosmology and plasma physics, studying the origin of magnetic fields in the universe. We formulate a canonical vorticity framework to investigate kinetic plasma physics-based magnetogenesis processes in a collisionless plasma. By considering canonical vorticity, a weighted sum of the fluid vorticity and the magnetic field as the canonical variable, this framework unifies several magnetogenesis processes, including the Biermann battery, the Weibel instability, and predicts several new pressure tensorial configurations as the fundamental source of self-generated magnetic field and vorticity in plasma. The framework is further extended to relativistic regime where an additional source of canonical vorticity, termed as kineclinicity effect, is identified. The theoretical predictions are systematically validated using particle-in-cell simulations, highlighting their implications for laboratory and astrophysical plasma environments.

physics.plasm-ph↗

arXiv2026

Kineclinic magnetogenesis in relativistic collisionless plasmas

The relativistic momentum equation of a collisionless plasma is reformulated to describe the time evolution of canonical vorticity. Compared to the non-relativistic counterpart, an additional source term for canonical vorticity is identified, which embodies the misalignment between the fluid momentum and fluid velocity gradients. This kineclinic term breaks the frozen-in condition of canonical vorticity, thereby enabling generation or dissipation of magnetic fields and vorticity. We verify the role of this effect through particle-in-cell simulations of a modified Beltrami flow. Kineclinicity should be finite for all relativistic plasma systems due to the general lack of a functional relationship between fluid momentum and fluid velocity.

physics.plasm-ph↗