Direct Imaging of the HD 35841 Debris Disk: A Polarized Dust Ring from Gemini Planet Imager and an Outer Halo from HST /STIS

Thomas M. Esposito (1) , Gaspard Duchene (1, 2) , Paul Kalas (3, 4) , Malena Rice (1) , Elodie Choquet (5, 6) , Bin Ren (7, 8) , Marshall Perrin (8) , Christine H Chen (8) , Pauline Arriaga (9) , Eugene Chiang (10) , Eric L Nielsen (4, 11) , James R Graham (1) , Jason J Wang (1) , Robert J de Rosa (1) , Katherine B Follette (11, 12) , S. Mark Ammons , Megan Ansdell (1) , Vanessa P Bailey , Travis Barman , Juan Sebastián Bruzzone , Joanna Bulger , Jeffrey Chilcote , Tara Cotten , Rene Doyon , Michael P Fitzgerald , Stephen J Goodsell , Alexandra Z Greenbaum , Pascale Hibon (13) , Li-Wei Hung , Patrick Ingraham , Quinn Konopacky , James E Larkin , Bruce Macintosh , Jérôme Maire (14) , Franck Marchis , Christian Marois , Johan Mazoyer , Stanimir Metchev , Maxwell A Millar-Blanchaer , Rebecca Oppenheimer , David Palmer , Jennifer Patience , Lisa Poyneer , Laurent Pueyo (8) , Abhijith Rajan (15) , Julien Rameau , Fredrik T Rantakyrö , Dominic Ryan , Dmitry Savransky , Adam C Schneider , Anand Sivaramakrishnan (8) , Inseok Song , Rémi Soummer (8) , Sandrine Thomas , J. Kent Wallace , Kimberly Ward-Duong , Sloane Wiktorowicz , Schuyler Wolff

1 LBNL - Lawrence Berkeley National Laboratory [Berkeley]
2 IPAG - Institut de Planétologie et d'Astrophysique de Grenoble
3 Department of Mathematics [Berkeley]
4 SETI - Search for Extraterrestrial Intelligence Institute
5 Caltech Department of Astronomy [Pasadena]
6 JPL - Jet Propulsion Laboratory
7 JHU - Johns Hopkins University
8 STSci - Space Telescope Science Institute
9 Department of Physics and Astronomy [UCLA, Los Angeles]
10 EPS - Department of Earth and Planetary Science [UC Berkeley]
11 KIPAC - Kavli Institute for Particle Astrophysics and Cosmology
12 Physics and Astronomy Department, Amherst College
13 ESO - European Southern Observatory [Santiago]
14 LUAN - Laboratoire Universitaire d'Astrophysique de Nice
15 ASU - Arizona State University [Tempe]

We present new high resolution imaging of a light-scattering dust ring and halo around the young star HD 35841. Using spectroscopic and polarimetric data from the Gemini Planet Imager in H-band (1.6 µm), we detect the highly inclined (i = 85 •) ring of debris down to a projected separation of ∼12 au (∼0. 12) for the first time. Optical imaging from HST /STIS shows a smooth dust halo extending outward from the ring to >140 au (>1.4). We measure the ring's scattering phase function and polarization fraction over scattering angles of 22 •-125 • , showing a preference for forward scattering and a polarization fraction that peaks at ∼30% near the ansae. Modeling of the scattered-light disk indicates that the ring spans radii of ∼60-220 au, has a vertical thickness similar to that of other resolved dust rings, and contains grains as small as 1.5 µm in diameter. These models also suggest the grains have a low porosity, are more likely to consist of carbon than astrosilicates, and contain significant water ice. The halo has a surface brightness profile consistent with that expected from grains pushed by radiation pressure from the main ring onto highly eccentric but still bound orbits. We also briefly investigate arrangements of a possible inner disk component implied by our spectral energy distribution models, and speculate about the limitations of Mie theory for doing detailed analyses of debris disk dust populations.

Domaines: Planétologie et astrophysique de la terre [astro-ph.EP]

Thomas M. Esposito, Gaspard Duchene, Paul Kalas, Malena Rice, Elodie Choquet, et al.. Direct Imaging of the HD 35841 Debris Disk: A Polarized Dust Ring from Gemini Planet Imager and an Outer Halo from HST /STIS. The Astronomical Journal, 2018, 156 (2), pp.47. ⟨10.3847/1538-3881/aacbc9⟩. ⟨hal-02118171⟩