**
**Charles
E. Seyler, Jr.

Professor and
Associate Director of Academic Affairs, Electrical
and Computer Engineering

322 Rhodes Hall

Phone: 607/255-4967

E-mail: ces7@cornell.edu

B.A. 1970, M.A. 1972 (South Florida); Ph.D. 1975 (Iowa)

Upon completing his Ph.D. in plasma physics, Seyler spent two years at the Courant Institute of Mathematical Sciences, at New York University working in fusion-related plasma physics. He then went to Los Alamos National Laboratory, where he worked as a research scientist in the controlled-fusion theory group. In 1981 he accepted a position in the School of Electrical Engineering at Cornell.

Our research interests are in the theory and simulation of nonlinear plasma phenomena, with a focus in the area of space-plasma-related research. Studies in terrestrial space plasma physics are concerned with the coupling of the earth's ionosphere and magnetosphere through electrodynamic processes involving waves that propagate between these regions. A primary goal is to understand certain aspects of the phenomenon known as the aurora. I am particularly interested in the electron acceleration process that produces the northern lights, and in the dynamical motion of the magnetospheric and ionospheric plasma that is responsible for the complex space and time structure in auroral displays

Interpretation of space-plasma-related phenomena is based on a three-pronged approach involving experiment, theory, and simulation. Data obtained from an experiment or "campaign" are applied to the development of a mathematical theory for the derivation of an approximate model of the observed phenomena. The basis for the structure of the model may vary from the well-understood behavior of a single particle in a magnetic field to the complex behavior of a complete three-dimensional representation. The analysis is focused on some aspect of the data that is not well understood; reasonable assumptions are adopted to make possible the development of a relatively simple model; and a computer simulation of the applicable differential equations is performed, interpreted, and compared to the experiment. This approach has resulted in considerable success in understanding the physical phenomena occurring in the space-plasma environment.

We have investigated problems related to space-plasma physics such as equatorial spread-F, auroral Alfven waves and electron acceleration, parametric decay of auroral kilometric radiation, and lower hybrid wave phenomena. All of these research topics are oriented towards understanding the space plasma environment.

- Theory and
Simulation of Magnetospheric-Ionospheric Coupling Dynamics
*(National Science Foundation)* - Theory and
simulation of lower hybrid waves and associated ion acceleration
in the auroral region
*(National Aeronautics and Space Administration)* - Theoretical
and Experimental Study of the Bottomside F-Region
*(Rome Laboratory, U. S. Air Force)*

- Kintner,
P. M., and C. L. Seyler. 1985. The status of observations and
theory of high latitude ionospheric and magnetospheric plasma
turbulence.
*Space Science Reviews*41:91-129. - Zargham,
Z., and C. E. Seyler. 1989. Collisional and inertial dynamics
of the ionospheric interchange instability.
*Journal of Geophysical Research*95:9009-27. - Seyler, C.
E. 1990. Mathematical model of the structure and evolution of
small-scale discrete auroral arcs.
*Journal of Geophysical Research*95:17199-17215. - Hui, C.-H.,
and C. E. Seyler. 1992. Electron acceleration by Alfven waves
in the magnetosphere.
*Journal of Geophysical Research*97:3953-63. - Seyler, C.
E. 1994. Lower-hybrid wave phenomena associated with density depletions.
*Journal of Geophysical Research*99:19513-26. - Seyler, C.
E. 1996. On the most probable states of two-dimensional plasmas.
*Journal of Plasma Physics*56:553-67. - Pincon, J.
L., P. N. Kintner, P. W. Schuck, and C. E. Seyler. Observation
and analysis of lower hybrid solitary structures as rotating eigenmodes.
*Journal of Geophysical Research*102(A8):17283-96.