The PDS 66 Circumstellar Disk as Seen in Polarized Light with the Gemini Planet Imager
Schneider, Glenn; Duchêne, Gaspard; Dong, Ruobing; Wolff, Schuyler G.; Kalas, Paul; Fitzgerald, Michael P.; Hines, Dean C.; Macintosh, Bruce; Millar-Blanchaer, Maxwell A.; Nielsen, Eric L.; Pueyo, Laurent; Rantakyrö, Fredrik T.; Graham, James R.; Marchis, Franck; Grady, Carol A.; Sivaramakrishnan, Anand; Draper, Zachary H.; Marois, Christian; Chilcote, Jeffrey; Wang, Jason; Goodsell, Stephen J.; Greenbaum, Alexandra Z.; Hibon, Pascale; Hung, Li-Wei; Perrin, Marshall; Wiktorowicz, Sloane J.; Hartung, Markus; Cardwell, Andrew
United States, Canada, Chile, France
Abstract
We present H- and K-band imaging polarimetry for the PDS 66 circumstellar disk obtained during the commissioning of the Gemini Planet Imager (GPI). Polarization images reveal a clear detection of the disk in to the 0.″12 inner working angle (IWA) in the H band, almost three times closer to the star than the previous Hubble Space Telescope (HST) observations with NICMOS and STIS (0.″35 effective IWA). The centro-symmetric polarization vectors confirm that the bright inner disk detection is due to circumstellar scattered light. A more diffuse disk extends to a bright outer ring centered at 80 AU. We discuss several physical mechanisms capable of producing the observed ring + gap structure. GPI data confirm enhanced scattering on the east side of the disk that is inferred to be nearer to us. We also detect a lateral asymmetry in the south possibly due to shadowing from material within the IWA. This likely corresponds to a temporally variable azimuthal asymmetry observed in HST/STIS coronagraphic imaging.