Description
We present the stellar population, using Gaia DR2 parallax, kinematics, and photometry, of the young (~100Myr), nearby (~230pc) open cluster, Blanco 1. A total of 644 member candidates are identified via the unsupervised machine learning method StarGO to find the clustering in the 5-dimensional position and proper motion parameter (X, Y, Z, {mu}{alpha}*cos{delta}, {mu}{delta}) space. Within the tidal radius of 10.0+/-0.3pc, there are 488 member candidates, 3 times more than those outside. A leading tail and a trailing tail, each of 50-60pc in the Galactic plane, are found for the first time for this cluster, with stars further from the cluster center streaming away faster, manifest stellar stripping. Blanco 1 has a total detected mass of 285+/-32M_{sun}_ with a mass function consistent with a slope of alpha=1.35+/-0.2 in the sense of dN/dm{prop.to}m^-alpha^, in the mass range of 0.25-2.51M_{sun}_, where N is the number of members and $m$ is stellar mass. A Minimum Spanning Tree ({LAMBDA}_MSR_) analysis shows the cluster to be moderately mass segregated among the most massive members (>~1.4M_{sun}_), suggesting an early stage of dynamical disintegration.
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