Date of Award
Spring 2024
Document Type
Thesis
Terms of Use
© 2024 Solomon Murdock. This work is freely available courtesy of the author. It may be used under the terms of the Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) license. For all other uses, please contact the copyright holder.
Creative Commons License
This work is licensed under a Creative Commons Attribution-Share Alike 4.0 International License.
Degree Name
Bachelor of Arts
Department
Physics & Astronomy Department
First Advisor
Michael R. Brown
Abstract
Many plasmas can be described by ideal magnetohydrodynamics (MHD). A key result of ideal MHD is the frozen-in-flux theorem which states that the magnetic field stretches and bends with the motion of the plasma. The frozen-in-flux theorem is violated during magnetic reconnection, the annihilation of magnetic flux within a plasma. During reconnection, non-ideal MHD effects dominate plasma dynamics. The dynamics of magnetic reconnection is an unsolved problem in plasma physics. Most prior laboratory studies of magnetic reconnection examined reconnection in 2D scenarios, scenarios with a single ignorable coordinate. The SSX device was used to merge twisted ropes of plasma called Taylor states which undergo 3D magnetic reconnection, reconnection without an ignorable coordinate, as they collide. The merging occurs in an unconfined volume at the center of SSX. The experiment measured the line averaged electron density and ion temperature along two different chords in the SSX midplane and measured the magnetic field on a grid of 16 coplanar positions in the merging region. We recorded data on 604 instances of Taylor state merging. The merging of Taylor states involves oscillations in density, magnetic energy, and ion temperature. Each quantity attains multiple significant peaks during each shot. The geometry of the current density in the merging region varies over the course of each shot. We calculated 11 summary statistics for each shot including the average and peak density, ion temperature, and magnetic energy and report their distributions. Neither average or peak magnetic energy is correlated with average or peak ion temperature despite ion heating being a known consequence of magnetic reconnection. The merging of Taylor states is much more complex and dynamic than two-dimensional magnetic reconnection.
Recommended Citation
Murdock, Solomon , '24, "Large Sample Statistical Study of Three-Dimensional Magnetic Reconnection at the Swarthmore Spheromak Experiment" (2024). Senior Theses, Projects, and Awards. 951.
https://works.swarthmore.edu/theses/951