Small vs. large dust grains in transitional disks: do different cavity sizes indicate a planet? - SAO 206462 (HD 135344B) in polarized light with VLT/NACO

TLDR: In this article, the surface structures in the surface layer of transitional disks were resolved using polarimetric differential imaging (PDE) observations of SAO 206462 (HD135344B).

Abstract: Context. Transitional disks represent a short stage of the evolution of circumstellar material. Studies of dust grains in these objects can provide pivotal information on the mechanisms of planet formation. Dissimilarities in the spatial distribution of small (μm−size) and large (mm−size) dust grains have recently been pointed out. Aims. Constraints on the small dust grains can be obtained by imaging the distribution of scattered light at near-infrared wavelengths. We aim at resolving structures in the surface layer of transitional disks (with particular emphasis on the inner 10−50 AU), thus increasing the scarce sample of high-resolution images of these objects. Methods. We obtained VLT/NACO near-IR high-resolution polarimetric differential imaging observations of SAO 206462 (HD135344B). This technique allows one to image the polarized scattered light from the disk without any occulting mask and to