Date of Award
2025
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Space Science
Committee Chair
Haihong Che
Committee Member
Gary Zank
Committee Member
Arnold Benz
Committee Member
Jakobus Le Roux
Committee Member
P.S. Athiray
Research Advisor
Haihong Che
Subject(s)
Solar flares, Particle acceleration, Magnetic reconnection, Space plasmas
Abstract
The origin of solar energetic electrons has been a long-standing problem, namely the production of a huge number of energetic electrons with power-law energy spectra within a sufficiently short time. Using particle-in-cell (PIC) magnetic reconnection (MR) simulations based on a new vortical electron acceleration model proposed by Che and Zank (CZ) [21], I first investigated the scaling of the PIC MR simulations to the observational scales of solar flares. The CZ model reproduced the sharp two-stage transition observed in soft-hard-harder electron energy spectra, implying that the electron acceleration timescale must be a small fraction of the solar flare duration. Then I investigated the impact of the magnetic guide field on the electron acceleration. I discovered that while the CZ model works well for smaller guide field MR, a new Alfv ́enic-like Fermi electron acceleration mechanism emerges for strong guide field MR, producing a harder power-law energy spectrum.
Recommended Citation
Crawford, Christopher, "Nonlinear vortical electron acceleration in magnetic reconnection and its application to solar flares" (2025). Dissertations. 453.
https://louis.uah.edu/uah-dissertations/453
