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

TL;DR

This paper investigates the kinematics of LP 543-25, a low-mass runaway star, using Gaia DR2 data, revealing its high velocity and likely origin from a star cluster in the Milky Way's inner regions.

Contribution

It provides a detailed kinematic analysis of LP 543-25, identifying it as a rare low-mass runaway star and clarifying its possible origin in the Galactic inner regions.

Findings

LP 543-25 has high Galactic velocity components (U, V, W) = (206, -289, 30) km/s.

It is moving away from the Galactic Center at nearly 200 km/s.

It is one of the closest and least massive runaway stars identified.

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.