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arXiv · 1908.00006

An Exo-Kuiper Belt and An Extended Halo around HD 191089 in Scattered Light

Abstract

We have obtained Hubble Space Telescope STIS and NICMOS, and Gemini/GPI scattered light images of the HD 191089 debris disk. We identify two spatial components: a ring resembling Kuiper Belt in radial extent (FWHM: ${\sim}$25 au, centered at ${\sim}$46 au), and a halo extending to ${\sim}$640 au. We find that the halo is significantly bluer than the ring, consistent with the scenario that the ring serves as the "birth ring" for the smaller dust in the halo. We measure the scattering phase functions in the 30{\deg}-150{\deg} scattering angle range and find the halo dust is both more forward- and backward-scattering than the ring dust. We measure a surface density power law index of -0.68${\pm}$0.04 for the halo, which indicates the slow-down of the radial outward motion of the dust. Using radiative transfer modeling, we attempt to simultaneously reproduce the (visible) total and (near-infrared) polarized intensity images of the birth ring. Our modeling leads to mutually inconsistent results, indicating that more complex models, such as the inclusion of more realistic aggregate particles, are needed.

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Bin Ren, Élodie Choquet, Marshall D. Perrin, Gaspard Duchêne, John H. Debes, Laurent Pueyo, Malena Rice, Christine Chen, Glenn Schneider, Thomas M. Esposito, Charles A. Poteet, Jason J. Wang, S. Mark Ammons, Megan Ansdell, Pauline Arriaga, Vanessa P. Bailey, Travis Barman, Juan Sebastián Bruzzone, Joanna Bulger, Jeffrey Chilcote, Tara Cotten, Robert J. De Rosa, Rene Doyon, Michael P. Fitzgerald, Katherine B. Follette, Stephen J. Goodsell, Benjamin L. Gerard, James R. Graham, Alexandra Z. Greenbaum, J. Brendan Hagan, Pascale Hibon, Dean C. Hines, Li-Wei Hung, Patrick Ingraham, Paul Kalas, Quinn Konopacky, James E. Larkin, Bruce Macintosh, Jérôme Maire, Franck Marchis, Christian Marois, Johan Mazoyer, François Ménard, Stanimir Metchev, Maxwell A. Millar-Blanchaer, Tushar Mittal, Magaret Moerchen, Eric L. Nielsen, Mamadou N'Diaye, Rebecca Oppenheimer, David Palmer, Jennifer Patience, Christophe Pinte, Lisa Poyneer, Abhijith Rajan, Julien Rameau, Fredrik T. Rantakyrö, Jean-Baptiste Ruffio, Dominic Ryan, Dmitry Savransky, Adam C. Schneider, Anand Sivaramakrishnan, Inseok Song, Rémi Soummer, Christopher Stark, Sandrine Thomas, Arthur Vigan, J. Kent Wallace, Kimberly Ward-Duong, Sloane Wiktorowicz, Schuyler Wolff, Marie Ygouf, Colin Norman. 2019-07-31. An Exo-Kuiper Belt and An Extended Halo around HD 191089 in Scattered Light. https://doi.org/10.3847/1538-4357/ab3403

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