Modeling the Structures of Dusty Disks: Unseen Planets?

One of the legacies of IRAS was to show that some 15% of main sequence stars are surrounded by disks of dust. The dust in these debris disks is continually replenished by the destruction of larger planetesimals and so these disks have the potential to tell us a great deal about the outcome of planet formation in their systems. To extract such information the disks need to be resolved. The handful of disks which have had their structure mapped have shown that none of these disks are smooth or axially symmetric. A wide variety of disk structures have been detected, ranging from warped disks of asymmetric brightness to clumpy ring‐like disks. Detailed dynamical modeling has identified many of these structures with perturbations from as yet unseen planetary companions. In this paper I review the types of structure that planets can, and indeed have been purported to, impose on debris disks, and look at the evidence we have from modeling of debris disk images that these unseen companions really exist.