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Training and Research Experiences in Nonlinear Dynamics

Theoretical and Computational Studies of Magnetic Reconnection and the Dynamics of Energetic Particles

James F. Drake and Marc Swisdak

The release of magnetic energy drives explosive phenomena throughout nature, including laboratory fusion experiments, storms in the Earth's magnetosphere, and astrophysical flares. Each is triggered by magnetic reconnection, where oppositely-directed magnetic field lines form an x-line configuration that changes the global topology and triggers the redirection of energy to the surrounding plasma. Magnetic reconnection is important in essentially all magnetized plasma systems ranging from the astrophysical environment to laboratory fusion experiments. The balance between the generation of magnetic field energy through the dynamo action of plasma flows and the dissipation of this energy through magnetic reconnection ultimately controls the size of the magnetic fields which are present in the universe. Magnetic reconnection is also intrinsically interesting because the change in topology of the magnetic field occurs in narrow boundary layers where the kinetic dynamics of waves and particles must be included to model the system.

The forefront of current research on magnetic reconnection is in the development of nonlinear 3-D turbulence in small-scale boundary layers and the production of large numbers of relativistic particles. The Drake-Swsidak group investigates these topics via massively parallel computations on some of the world's largest supercomputers.

Students will have the opportunity to interat with scientists at all levels of the research project. They will be introduced to plasma physics (particuarly space plasmas), become familiar with running massively parallel codes, and learn how to carry out a scientific investigation. Care will be taken to match the complexity of the problem with the skills and time available so that students can bring projects to completion, leading to the publication of their results in a peer-reviewed journal.

A project which could involve undergraduate participation is the self-generation of regions of intense electric field by strong electron beams and the resulting scattering of these beams. This interesting and complex dynamical system can be explored through computer simulation and analytic theory. Visualization of complex data systems to extract the important dynamics is an essential ingredient to advancing the field.

Additional information about magnetic reconnection and the dynamics of energetic particles can be found at http://www.terpconnect.umd.edu/~drake/ and by contacting James Drake at 301-405-1471 or drake@umd.edu or Marc Swisdak at 301-405-1495 or swisdak@umd.edu.