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

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 نشر من قبل Sergio Abraham Dzib Quijano
 تاريخ النشر 2018
  مجال البحث فيزياء
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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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