ASA 126th Meeting Denver 1993 October 4-8

1pUW11. Higher-order perturbation theory versus the scattering operator expansion method for 3-D surface scattering.

John Dubberley

NRL Code 7181, Stennis Space Center, MS 39529-5004

Jorge Novarini

Planning Systems, Inc., Bay St. Louis, MS

Richard Keiffer

NRL, Stennis Space Center, MS 39529-5004

To this point little work available in the literature has examined whether three-dimensional scattering events can be successfully modeled by a two-dimensional stimulation. This has mainly been caused by a lack of sufficient computational and modeling power in the past. A contributing reason to the low interest in the validity of this assumption is that there seems to be no compelling reason why the two-dimensional assumption would fail to correctly approximate the three-dimensional situation. However, in the interest of completeness, the ramifications of this assumption must be explored. Here two models are used to provide a preliminary look at this issue. Perturbation theory and the scattering operator expansion surface scattering methods will be compared to each other over a variety of canonical and ``realistic'' surfaces. The strengths and weaknesses of each model for this task will be mentioned. Up to third-order implementations of these methods will be used.