Images of the Extended Outer Regions of the Debris Ring around HR 4796 A

Abstract

Vega-type debris disks were first identified by infrared (IR) excesses around nearby main sequence stars [1]. The dust content of these second-generation disk systems is believed to be continuously replenished via collisional breakup of remnant planetesimals [2]. Since the imaging of the β Pic system [3], nearly two dozen nearby debris disks have been spatially resoved. The morphological appearance of resolved debris disks is predicted by several mechanisms, e.g., interactions between dust in the disk and nearby planets [4]. We present high-contrast images of HR 4796A taken with Subaru/HiCIAO in H-band, resolving the debris disk in scattered light[4]. HR 4796A is a young (~8– 10 Myr; [5]), nearby (72.8 ± 1.7 pc; [6]), A0V-type star first identified as a debris disk system from an IR excess