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arXiv · 1005.3830

Herschel-PACS observation of the 10 Myr old T Tauri disk TW Hya: Constraining the disk gas mass

W. F. Thi·G. Mathews·F. Ménard·P. Woitke·G. Meeus·P. Riviere-Marichalar·C. Pinte·C. D. Howard·A. Roberge·G. Sandell·I. Pascucci·B. Riaz·C. A. Grady·W. R. F. Dent·I. Kamp·G. Duchêne·J. C. Augereau·E. Pantin·B. Vandenbussche·I. Tilling·J. P. Williams·C. Eiroa·D. Barrado·J. M. Alacid·S. Andrews·D. R. Ardila·G. Aresu·S. Brittain·D. R. Ciardi·W. Danchi·D. Fedele·I. de Gregorio-Monsalvo·A. Heras·N. Huelamo·A. Krivov·J. Lebreton·R. Liseau·C. Martin-Zaidi·I. Mendigutía·B. Montesinos·A. Mora·M. Morales-Calderon·H. Nomura·N. Phillips·L. Podio·D. R. Poelman·S. Ramsay·K. Rice·E. Solano·H. Walker·G. J. White·G. Wright
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Abstract

Planets are formed in disks around young stars. With an age of ~10 Myr, TW Hya is one of the nearest T Tauri stars that is still surrounded by a relatively massive disk. In addition a large number of molecules has been found in the TW Hya disk, making TW Hya the perfect test case in a large survey of disks with Herschel-PACS to directly study their gaseous component. We aim to constrain the gas and dust mass of the circumstellar disk around TW Hya. We observed the fine-structure lines of [OI] and [CII] as part of the Open-time large program GASPS. We complement this with continuum data and ground-based 12CO 3-2 and 13CO 3-2 observations. We simultaneously model the continuum and the line fluxes with the 3D Monte-Carlo code MCFOST and the thermo-chemical code ProDiMo to derive the gas and dust masses. We detect the [OI] line at 63 micron. The other lines that were observed, [OI] at 145 micron and [CII] at 157 micron, are not detected. No extended emission has been found. Preliminary modeling of the photometric and line data assuming [12CO]/[13CO]=69 suggests a dust mass for grains with radius < 1 mm of ~1.9 times 10^-4 Msun (total solid mass of 3 times 10^-3 Msun) and a gas mass of (0.5--5) times 10^-3 Msun. The gas-to-dust mass may be lower than the standard interstellar value of 100.

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W. F. Thi, G. Mathews, F. Ménard, P. Woitke, G. Meeus, P. Riviere-Marichalar, C. Pinte, C. D. Howard, A. Roberge, G. Sandell, I. Pascucci, B. Riaz, C. A. Grady, W. R. F. Dent, I. Kamp, G. Duchêne, J. C. Augereau, E. Pantin, B. Vandenbussche, I. Tilling, J. P. Williams, C. Eiroa, D. Barrado, J. M. Alacid, S. Andrews, D. R. Ardila, G. Aresu, S. Brittain, D. R. Ciardi, W. Danchi, D. Fedele, I. de Gregorio-Monsalvo, A. Heras, N. Huelamo, A. Krivov, J. Lebreton, R. Liseau, C. Martin-Zaidi, I. Mendigutía, B. Montesinos, A. Mora, M. Morales-Calderon, H. Nomura, N. Phillips, L. Podio, D. R. Poelman, S. Ramsay, K. Rice, E. Solano, H. Walker, G. J. White, G. Wright. 2010-05-20. Herschel-PACS observation of the 10 Myr old T Tauri disk TW Hya: Constraining the disk gas mass. https://doi.org/10.1051/0004-6361/201014578

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