Protostars and Planets VI, Heidelberg, July 15-20, 2013
Poster 2B052
Constraining the structure of the transition disk HD 135344B (SAO 206462) by simultaneous modeling of multi-wavelength gas and dust observations
Carmona, Andres (UJF-Grenoble 1 / CNRS-INSU, Institut de Planétologie et d’Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble, F-38041)
Christophe, Pinte (UJF-Grenoble 1 / CNRS-INSU, Institut de Planétologie et d’Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble, F-38041)
Thi, Wing Fai (UJF-Grenoble 1 / CNRS-INSU, Institut de Planétologie et d’Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble, F-38041)
Myriam , Benisty (UJF-Grenoble 1 / CNRS-INSU, Institut de Planétologie et d’Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble, F-38041)
Menard, Francois (UJF-Grenoble 1 / CNRS-INSU, Institut de Planétologie et d’Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble, F-38041)
Grady, Carol (Eureka Scientific, 2452 Delmer, Suite 100, Oakland CA 96002, USA; ExoPlanets and Stellar Astrophysics Laboratory, Code 667, Goddard Space Flight Center, Greenbelt, MD 20771, USA )
Kamp , Inga (Kapteyn Astronomical Institute, P.O. Box 800, 9700 AV Groningen, The Netherlands)
Peter, Woitke (SUPA, School of Physics and Astronomy, University of St. Andrews, KY16 9SS, UK)
Olofsson, Johan (Max Planck Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg, Germany)
Roberge, Aki (Goddard Center for Astrobiology, Goddard Space Flight Center, Greenbelt, MD 20771, USA)
Brittain, Sean (Department of Physics & Astronomy, 118 Kinard Laboratory, Clemson University, Clemson, SC 29634, USA)
Duchene, Gaspard (Astronomy Department, University of California, Berkeley, CA 94720-3411, USA; UJF-Grenoble 1 /CNRS-INSU, Institut de Planétologie et d\'Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble, F-38041)
Meeus, Gwendolyn (Departamento de Fisica Teorica,Universidad Autonoma de Madrid, Campus Cantoblanco, Spain)
Martin-Zaïdi, Claire (UJF-Grenoble 1 /CNRS-INSU, Institut de Planétologie et d\'Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble, F-38041)
Dent, Bill (Joint ALMA Observatory, Alonso de Córdova 3107, Vitacura 763-0355, Santiago, Chile)
Le Bouquin, Jean Baptiste (UJF-Grenoble 1 /CNRS-INSU, Institut de Planétologie et d\'Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble, F-38041)
Berger, Jean Philippe (UJF-Grenoble 1 /CNRS-INSU, Institut de Planétologie et d\'Astrophysique de Grenoble (IPAG) UMR 5274, Grenoble, F-38041)
Abstract:
Constraining the gas and dust disk structure of transition disks, particularly in the inner dust cavity, is a crucial step towards understanding the link between them and planet formation. HD 135344B is an accreting (pre-) transition disk that displays emission of warm CO inside its dust cavity. We employ the dust radiative transfer code MCFOST and the thermo-chemical code ProDiMo to derive the disk structure from the simultaneous modeling of the spectral energy distribution (SED), VLT/CRIRES CO P(10) 4.75 micron, Herschel/PACS [OI] 63 micron, Spitzer-IRS, and JCMT 12CO J=3-2 spectra, VLTI/PIONIER H-band visibilities, and constraints from (sub-)mm continuum interferometry and near-IR imaging.
Results: (1) A gaseous inner disk extending up to 30 AU with silicate grains (M < 10-7 Msun) enriched with carbonaceous grains (M < 10^-12 Msun) at a fraction of AU can describe simultaneously the SED, the CO P(10) line profile, and the 870 micron continuum at R < 30 AU. Inner disk models assuming only astronomical silicates or a constant carbon/silicates ratio do not reproduce the CO P(10) line profile. (2) To fit the near-IR visibilities the carbonaceous grains enrichment should be located inside the silicates sublimation radius (0.08 < R < 0.2 AU); (3) The surface density distribution of the gas at R<30 AU (i.e. inside the dust cavity) must increase with radius to fit the CO P(10) line profile. The gas mass at R<30 AU is 10^-5 - 10^-4 Msun, thus a gas-to-dust ratio >100. (4) In the outer disk (30 < R < 200 AU) most of the gas and dust mass should be in the mid-plane to simultaneously fit the SED and the [OI] 63 micron line flux. (5) The gas-to-dust ratio in the outer disk should be < 50 (gas mass 2 - 50 × 10^-4 Msun) to reproduce simultaneously the [OI] 63 micron line flux and the CO P(10) line profile. (6) A gap of few AU between the inner and outer disk is compatible with current data.
Simultaneous modeling of gas and dust breaks model degeneracies and constrains the disk structure. An increasing gas surface density as a function of the radius in the inner dust cavity echoes the effect of a migrating jovian planet in the disk structure. The low gas mass in the HD 135344B disk supports the idea that it is an evolved object. The disk structure proposed for HD 135344B could be applied to other pre-transitional disks with CO ro-vibrational emission extending several AU.
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