Particle Dynamics in a Starved Pulsar Magnetosphere: A Dedalus-PIC Simulation Study 86 views

Pulsar magnetospheres host some of the strongest electromagnetic fields in nature and can accelerate charged particles to ultra-relativistic energies. An important stage in magnetospheric formation occurs when the region above the neutron-star surface is initially starved of plasma, which permits unscreened accelerating electric fields. Such vacuum gaps are widely believed to trigger pair cascades that ultimately populate and regulate pulsar magnetospheres. In this thesis, I study particle acceleration in a charge-starved environment by evolving relativistic electron-positron pairs in analytically prescribed vacuum electromagnetic fields, evaluated using a Dedalus-based spectral framework. The simulations exhibit latitude-dependent charge separation: symmetric positron outflows from both poles, electron outflows from mid-latitudes, and a trapped equatorial dead zone. These results demonstrate that vacuum-field electrodynamics robustly sorts charges by latitude, and they provide insight into the early plasma-formation phase that precedes the development of a force-free magnetosphere.

BS (Bachelor of Science)

Dedalus Project; Pseudospectral Methods; Particle-In-Cell; Boris Pusher; Hybrid Simulations; Pulsar Magnetospheres; Neutron Stars; Vacuum Gap Models; Relativistic Electrodynamics; Unipolar Induction; Goldreich-Julian Model; Charge Separation; Magnetic Mirroring; Polar Outflows

English

2026-05-08