%0 Journal Article
%T $¦Â$ Pictoris' inner disk in polarized light and new orbital parameters for $¦Â$ Pictoris b
%A Maxwell A. Millar-Blanchaer
%A James R. Graham
%A Laurent Pueyo
%A Paul Kalas
%A Rebekah I. Dawson
%A Jason Wang
%A Marshall Perrin
%A Dae-Sik Moon
%A Bruce Macintosh
%A S. Mark Ammons
%A Travis Barman
%A Andrew Cardwell
%A Christine H. Chen
%A Eugene Chiang
%A Jeffrey Chilcote
%A Tara Cotten
%A Robert J. De Rosa
%A Zachary H. Draper
%A Jennifer Dunn
%A Gaspard Duch¨ºne
%A Thomas M. Esposito
%A Michael P. Fitzgerald
%A Katherine B. Follette
%A Stephen J. Goodsell
%A Alexandra Z. Greenbaum
%A Markus Hartung
%A Pascale Hibon
%A Sasha Hinkley
%A Patrick Ingraham
%A Rebecca Jensen-Clem
%A Quinn Konopacky
%A James E. Larkin
%A Douglas Long
%A J¨¦r£¿me Maire
%A Franck Marchis
%A Mark S. Marley
%A Christian Marois
%A Katie M. Morzinski
%A Eric L. Nielsen
%A David W. Palmer
%A Rebecca Oppenheimer
%A Lisa Poyneer
%A Abhijith Rajan
%A Fredrik T. Rantakyr£¿
%A Jean-Baptiste Ruffio
%A Naru Sadakuni
%A Leslie Saddlemyer
%A Adam C. Schneider
%A Anand Sivaramakrishnan
%A Remi Soummer
%A Sandrine Thomas
%A Gautam Vasisht
%A David Vega
%A J. Kent Wallace
%A Kimberly Ward-Duong
%A Sloane J. Wiktorowicz
%A Schuyler G. Wolff
%J Physics
%D 2015
%I arXiv
%R 10.1088/0004-637X/811/1/18
%X We present $H$-band observations of $\beta$ Pic with the Gemini Planet Imager's (GPI's) polarimetry mode that reveal the debris disk between ~0.3" (~6 AU) and ~1.7" (~33 AU), while simultaneously detecting $\beta$ Pic $b$. The polarized disk image was fit with a dust density model combined with a Henyey-Greenstein scattering phase function. The best fit model indicates a disk inclined to the line of sight ($\phi=85.27{\deg}^{+0.26}_{-0.19}$) with a position angle $\theta_{PA}=30.35{\deg}^{+0.29}_{-0.28}$ (slightly offset from the main outer disk, $\theta_{PA}\approx29{\deg}$), that extends from an inner disk radius of $23.6^{+0.9}_{-0.6}$ AU to well outside GPI's field of view. In addition, we present an updated orbit for $\beta$ Pic $b$ based on new astrometric measurements taken in GPI's spectroscopic mode spanning 14 months. The planet has a semi-major axis of $a=9.2^{+1.5}_{-0.4}$AU, with an eccentricity $e\leq 0.26$. The position angle of the ascending node is $\Omega=31.75{\deg}\pm0.15$, offset from both the outer main disk and the inner disk seen in the GPI image. The orbital fit constrains the stellar mass of $\beta$ Pic to $1.60\pm0.05 M_{\odot}$. Dynamical sculpting by $\beta$ Pic $b$ cannot easily account for the following three aspects of the inferred disk properties: 1) the modeled inner radius of the disk is farther out than expected if caused by $\beta$ Pic b; 2) the mutual inclination of the inner disk and $\beta$ Pic $b$ is $4{\deg}$, when it is expected to be closer to zero; and 3) the aspect ratio of the disk ($h_0 = 0.137^{+0.005}_{-0.006}$) is larger than expected from interactions with $\beta$ Pic $b$ or self-stirring by the disk's parent bodies.
%U http://arxiv.org/abs/1508.04787v1