Date of Award

Spring 1998

Document Type

Restricted Thesis

Terms of Use

© 1998 Thomas W. Kornack. All rights reserved. Access to this work is restricted to users within the Swarthmore College network and may only be used for non-commercial, educational, and research purposes. Sharing with users outside of the Swarthmore College network is expressly prohibited. For all other uses, including reproduction and distribution, please contact the copyright holder.

Degree Name

Bachelor of Arts

Department

Physics & Astronomy Department

First Advisor

Michael R. Brown

Abstract

Magnetic reconnection is the fundamental process by which magnetic fields in conductive fluids topologically rearrange themselves while moving to a lower energy state. Merging two parcels of magnetofluid with oppositely oriented magnetic fields causes the fields to be annihilated. Conservation of energy demands that magnetic energy be converted into the kinetic energy of the fluid, which is accelerated out of the reconnecting layer. The Swarthmore Spheromak Experiment (SSX) studies magnetic reconnect ion by merging two rings of plasma magnetofluid called spheromaks. The magnetic reconnection is observed using magnetic probes and the accelerated particles are measured using particle detectors. Magnetic reconnection events have been observed and show strong correlation with high energy particle flow out of the reconnecting layer of plasma. 1D and 2D maps of the time resolved magnetic field in the reconnection region are presented, showing the evolution of both X-points and O-points. These observations are used to compare various analytical and numerical models of reconnect ion. The Sweet-Parker (Sweet, 1958; Parker, 1957) resistive MHD model of reconnection is presented as a simple and well understood theory. Experimental observations of the size of the reconnection layer, however, do not agree with the resistive MHD prediction. A two-fluid collisionless theory by Biskamp et al. (1997) provides a good prediction of the scaling and a more detailed picture of the structure of the reconnection layer. Simulations by Matthaeus et al. (1984) show that turbulence can create O-points in the reconnection layer. Whereas these theories provide good macroscopic descriptions of reconnection, the actual physical mechanism for reconnection at the microscopic scale remains unknown. This thesis also includes supporting material on a fast gas valve design, triple probe analysis, and spheromak formation studies in the appendices.

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