Howard G. Demars

Research Associate Professor,

Physics Department
Center for Atmospheric and Space Sciences

B.S. Physics, Utah State University, 1976

M. S., Physics, Utah State University, 1978

Ph.D., Physics, Utah State University, 1986

Dr. Demars received his B.S. and M.S. degrees in Physics at Utah State University in 1976 and 1978, respectively. After working for two years as a physicist for Hughes Aircraft Company, where he modeled space shuttle self-contamination, he returned to USU, finishing his Ph.D. in 1986. Dr. Demars is presently a Research Associate Professor, having a joint appointment with the USU Physics Department and the Center for Atmospheric and Space Sciences.

Dr. Demars has worked extensively in the areas of generalized transport theory and kinetic theory. He has made contributions to the fundamental theory of bi-Maxwellian based 16-moment transport theory, and he has applied 16-moment and other transport theories to a wide range of problems in space physics, including subsonic flows in the ionosphere, heat flow processes along SAR-arc field lines, supersonic and subsonic flows in the polar wind, diffusion of minor species in the ionosphere, "quiet" solar wind flows, and plasma transport between Saturn's ionosphere and magnetosphere. This research has emphasized the self-consistent modeling of all of the major species of particular geophysical plasmas. Dr. Demars has constructed semikinetic models of the solar and polar winds, and he has performed comparative studies that help to clarify the relative strengths and weaknesses of the generalized transport, kinetic, and Monte Carlo approaches in space plasma applications. Also, Dr. Demars has used a macroscopic particle-in-cell code to study "non-classical" polar wind processes, such as shock formation, centrifugal acceleration, and the trapping of ions.

In recent years, Dr. Demars has used a 3D time-dependent fluid model of the coupled ionosphere and polar wind to simulate plasma dynamics on a fine grid (along > 1000 convecting flux tubes), for varying seasonal and solar cycle conditions. He has also used a 3D time-dependent model of the global thermosphere, developed at USU, to investigate the effects of mesoscale features of the ionosphere on the neutral atmosphere, including equatorial plasma bubbles and transpolar arcs. Most recently, Dr. Demars has coupled the 3D fluid model of the ionosphere and polar wind with the 3D thermosphere model in a self-consistent fashion and has begun to apply this combined thermosphere-ionosphere-polar wind model to problems of interest in space science. Dr. Demars is author or coauthor of 30 scientific publications.

Selected Publications

Demars, H. G., and R. W. Schunk, Seasonal and solar-cycle variations of the polar wind, J. Geophys. Res., 106, 8157-8168, 2001.

Demars, H. G., and R. W. Schunk, Three-dimensional velocity structure of the polar wind, J. Geophys. Res., 107, 1250-1270, 2002.

Schunk, R. W., and H. G. Demars, Effect of equatorial plasma bubbles on the thermosphere, J. Geophys. Res., 108, 1245-1252, 2003.

Demars, H. G., and R. W. Schunk, Effect of the theta aurora on the polar thermosphere, J. Atmos. Solar-Terr. Phys., submitted.