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arXiv · 1505.01947

Quantifying the gas inside dust cavities in transitional disks: implications for young planets

E. F. van Dishoeck·N. van der Marel·S. Bruderer·P. Pinilla
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Abstract

ALMA observations of a small sample of transitional disks with large dust cavities observed in Cycle 0 and 1 are summarized. The gas and dust surface density structures are inferred from the continuum and 12CO, 13CO and C18O line data using the DALI physical-chemical code. Thanks to its ability to self-shield, CO can survive inside dust cavities in spite of being exposed to intense UV radiation and can thus be used as a probe of the gas structure. Modeling of the existing data shows that gas is present inside the dust cavities in all cases, but at a reduced level compared with the gas surface density profile of the outer disk. The gas density decrease inside the dust cavity radius by factors of up to 10^4 suggests clearing by one or more planetary-mass companions. The accompanying pressure bumps naturally lead to trapping of the mm-sized dust grains observed in the ALMA images.

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E. F. van Dishoeck, N. van der Marel, S. Bruderer, P. Pinilla. 2015-05-08. Quantifying the gas inside dust cavities in transitional disks: implications for young planets. https://arxiv.org/abs/1505.01947

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