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arXiv · 1801.05231

VLBA Determination of the Distance to Nearby Star-forming Regions. VIII. The LkH$\alpha$ 101 cluster

S. A. Dzib·G. N. Ortiz-León·Laurent Loinard·A. J. Mioduszewski·L. F. Rodríguez·S. -N. X. Medina·R. M. Torres
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Abstract

The LkH$\alpha$ 101 cluster takes its name from its more massive member, the LkH$\alpha$ 101star, which is an $\sim15$ M$_\odot$ star whose true nature is still unknown. The distance to the LkH$\alpha$ 101 cluster has been controversial for the last few decades, with estimated values ranging from 160 to 800 pc. We have observed members and candidate members of the LkH$\alpha$ 101 cluster with signs of magnetic activity, using the Very Long Baseline Array, in order to measure their trigonometric parallax and, thus, obtain a direct measurement of their distances. A young star member, LkH$\alpha$ 101 VLA J043001.15+351724.6, was detected at four epochs as a single radio source. The best fit to its displacement on the plane of the sky yields a distance of 535$\pm$29 pc. We argue that this is the distance to the LkH$\alpha$ 101 cluster.

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S. A. Dzib, G. N. Ortiz-León, Laurent Loinard, A. J. Mioduszewski, L. F. Rodríguez, S. -N. X. Medina, R. M. Torres. 2018-01-16. VLBA Determination of the Distance to Nearby Star-forming Regions. VIII. The LkH$\alpha$ 101 cluster. https://doi.org/10.3847/1538-4357/aaa431

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