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arXiv · 1510.00739

Rings of C2H in the Molecular Disks Orbiting TW Hya and V4046 Sgr

J. H. Kastner·C. Qi·U. Gorti·P. Hily-Blant·K. Oberg·T. Forveille·S. Andrews·D. Wilner
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Abstract

We have used the Submillimeter Array to image, at ~1" resolution, C2H(3-2) emission from the molecule-rich circumstellar disks orbiting the nearby, classical T Tauri star systems TW Hya and V4046 Sgr. The SMA imaging reveals that the C2H emission exhibits a ring-like morphology within each disk, the inner hole radius of the C2H ring within the V4046 Sgr disk (~70 AU) is somewhat larger than than of its counterpart within the TW Hya disk (~45 AU). We suggest that, in each case, the C2H emission likely traces irradiation of the tenuous surface layers of the outer disks by high-energy photons from the central stars.

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J. H. Kastner, C. Qi, U. Gorti, P. Hily-Blant, K. Oberg, T. Forveille, S. Andrews, D. Wilner. 2015-10-02. Rings of C2H in the Molecular Disks Orbiting TW Hya and V4046 Sgr. https://doi.org/10.1017/s1743921315005979

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