PHASE CURVES OF SELECTED PARTICULATE MATERIALS : THE CONTRIBUTION OF COHERENT BACKSCATTERING TO THE OPPOSITION SURGE

摘要: Abstract We present angular scattering measurements of a suite particulate materials varying particle sizes and albedos over phase angles 1 Eight samples were each presented with both senses linearly circularly polarized light the reflectance circular polarization ratio as function angle was measured. The reflectances varied from 3 to 99%. observed increase in all observation decreased near 0° angle. traditional explanation opposition surge, shadow hiding model, predicts that should decrease decreases. more reflective exhibit stronger surge amplitudes than less ones. find non-linear relationship between slope curve measured at 2° single albedo sample which is opposite what predicted by model for effect. Our results are consistent predictions theoretical models coherent backscattering spherical particles strongly suggest major contributor They provide an surges reported highly media, also high icy satellites outer Solar System, cannot be explained model.