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arXiv · 1805.09357

The Gould's Belt Distances Survey (GOBELINS). IV. Distance, Depth and Kinematics of the Taurus Star-Forming Region

Phillip A. B. Galli·Laurent Loinard·Gisela N. Ortiz-Leon·Marina Kounkel·Sergio A. Dzib·Amy J. Mioduszewski·Luis F. Rodriguez·Lee Hartmann·Ramachrisna Teixeira·Rosa M. Torres·Juana L. Rivera·Andrew F. Boden·Neal J. Evans II·Cesar Briceno·John J. Tobin·Mark Heyer
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Abstract

We present new trigonometric parallaxes and proper motions of young stellar objects in the Taurus molecular cloud complex from observations collected with the Very Long Baseline Array as part of the Gould's Belt Distances Survey (GOBELINS). We detected 26 young stellar objects and derived trigonometric parallaxes for 18 stars with an accuracy of 0.3$\%$ to a few percent. We modeled the orbits of six binaries and determined the dynamical masses of the individual components in four of these systems (V1023 Tau, T Tau S, V807 Tau and V1000 Tau). Our results are consistent with the first trigonometric parallaxes delivered by the Gaia satellite and reveal the existence of significant depth effects. We find that the central portion of the dark cloud Lynds 1495 is located at $d=129.5\pm 0.3$ pc while the B 216 clump in the filamentary structure connected to it is at $d=158.1\pm 1.2$ pc. The closest and remotest stars in our sample are located at $d=126.6\pm 1.7$ pc and $d=162.7\pm 0.8$ pc yielding a distance difference of about 36 pc. We also provide a new distance estimate for HL Tau that was recently imaged. Finally, we compute the spatial velocity of the stars with published radial velocity and investigate the kinematic properties of the various clouds and gas structures in this region.

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Phillip A. B. Galli, Laurent Loinard, Gisela N. Ortiz-Leon, Marina Kounkel, Sergio A. Dzib, Amy J. Mioduszewski, Luis F. Rodriguez, Lee Hartmann, Ramachrisna Teixeira, Rosa M. Torres, Juana L. Rivera, Andrew F. Boden, Neal J. Evans II, Cesar Briceno, John J. Tobin, Mark Heyer. 2018-05-23. The Gould's Belt Distances Survey (GOBELINS). IV. Distance, Depth and Kinematics of the Taurus Star-Forming Region. https://doi.org/10.3847/1538-4357%2Faabf91

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