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arXiv · 1708.08122

An ALMA Dynamical Mass Estimate of the Proposed Planetary-mass Companion FW Tau C

Ya-Lin Wu·Patrick D. Sheehan
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Abstract

Dynamical mass estimates down to the planet-mass regime can help to understand planet formation. We present Atacama Large Millimeter/submillimeter Array (ALMA) 1.3 mm observations of FW Tau C, a proposed ~10 $M_{\rm Jup}$ planet-mass companion at ~330 au from the host binary FW Tau AB. We spatially and spectrally resolve the accretion disk of FW Tau C in ${}^{12}$CO (2-1). By modeling the Keplerian rotation of gas, we derive a dynamical mass of ~0.1 $M_\odot$. Therefore, FW Tau C is unlikely a planet, but rather a low-mass star with a highly inclined disk. This also suggests that FW Tau is a triple system consisting of three ~0.1 $M_\odot$ stars.

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Ya-Lin Wu, Patrick D. Sheehan. 2017-08-27. An ALMA Dynamical Mass Estimate of the Proposed Planetary-mass Companion FW Tau C. https://doi.org/10.3847/2041-8213/aa8771

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