BOUNDARY-ELEMENT METHOD CALCULATION FOR COHERENT ELECTROMAGNETIC SCATTERING FROM 2 AND 3 DIELECTRIC SPHERES

A quadratic, isoparametric boundary element formulation has been used to calculate the multiple scattering of electromagnetic waves from sys tems of two and three dielectric spheres. Extinction efficiency result s for the scattering of a plane wave are presented for variations of t he separation of the two spheres in three kinds of orientations of the system with respect to the incident wave. These have been verified ag ainst analytical calculations based on Mie's theory and calculations b y other authors. The results demonstrate a large side scattering reson ance (the so-called specular resonance). Agreement between the results establishes the boundary element method as a very powerful tool for s olving multiple scattering problems because the method applies to arbi trarily shaped objects having a homogeneous dielectric constant in any configuration. To illustrate the versatility of the method, scatterin g from three spheres is calculated.