TIME-RESOLVED MEASUREMENTS WHICH ISOLATE THE MECHANISMS RESPONSIBLE FOR TERAHERTZ GLORY SCATTERING FROM DIELECTRIC SPHERES

The surface-wave scattering processes responsible, in part, for the op tical glory have never been compared with theoretical predictions. Her e, THz impulse ranging is used to measure the time domain impulse resp onse of spherical targets with sufficiently high temporal resolution t o permit the surface-wave contribution to the total impulse response t o be isolated. The first direct experimental comparison for the surfac e wave with Mie theory as well as the surface-wave approximation of va n de Hulst is performed. Interference of the surface waves from a diel ectric sphere is shown to lead to the frequency and angular intensity dependence of the THz glory.