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arXiv · 1805.06423

LP 543-25: a rare low-mass runaway disk star

R. de la Fuente Marcos·C. de la Fuente Marcos
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Abstract

LP 543-25 or PSS 544-7 is a high proper-motion star located 458 pc from the Sun in the constellation of Canis Minor; it has been argued that it could be a candidate cannonball star ejected by a star cluster. Here, we revisit the issue of the kinematics of this interesting star using Gaia DR2. The heliocentric Galactic velocity components are (U, V, W) = (206, -289, 30) km/s; the corresponding Galactocentric Galactic velocity components show that LP 543-25 is moving in the Galactic plane and away from the Galactic Center at a rate of nearly 200 km/s, which is compatible with an origin in one of the multiple star clusters that inhabit the inner regions of the Milky Way. LP 543-25 appears to be a member of an elusive class of stars, the low-mass runaway stars. It is perhaps one of the closest and less massive runaway stars identified so far.

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R. de la Fuente Marcos, C. de la Fuente Marcos. 2018-05-16. LP 543-25: a rare low-mass runaway disk star. https://doi.org/10.3847/2515-5172%2Faac5d7

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