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arXiv · 1104.4806

Emission Lines from the Gas Disk around TW Hydra and the Origin of the Inner Hole

Uma Gorti·David Hollenbach·Joan Najita·Ilaria Pascucci
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Abstract

We compare line emission calculated from theoretical disk models with optical to sub-millimeter wavelength observational data of the gas disk surrounding TW Hya and infer the spatial distribution of mass in the gas disk. The model disk that best matches observations has a gas mass ranging from $\sim10^{-4}-10^{-5}$\ms\ for $0.06{\rm AU} 13.6$eV) flux from TW Hya. H$_2$ pure rotational line emission comes primarily from $r\sim 1-30$AU. [OI]63$\mu$m, HCO$^+$ and CO pure rotational lines all arise from the outer disk at $r\sim30-120$AU. We discuss planet formation and photoevaporation as causes for the decrease in surface density of gas and dust inside 4 AU. If a planet is present, our results suggest a planet mass $\sim 4-7$M$_J$ situated at $\sim 3$AU. Using our photoevaporation models and the best surface density profile match to observations, we estimate a current photoevaporative mass loss rate of $4\times10^{-9}$\ms\ yr$^{-1}$ and a remaining disk lifetime of $\sim 5$ million years.

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Uma Gorti, David Hollenbach, Joan Najita, Ilaria Pascucci. 2011-04-25. Emission Lines from the Gas Disk around TW Hydra and the Origin of the Inner Hole. https://doi.org/10.1088/0004-637x/735/2/90

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