Young, high-velocity a stars. II - Misidentified, ejected, or unique?

Lance, C. 1988, Ap. J. 334, 927.

The ages, abundances, and kinematics of a large number of early-type stars at the south Galactic pole are derived to examine the properties, augment the sample of high-velocity stars, and study hypotheses concerning their origin. The results are compared to a group of normal A stars near the disk. It is suggested that at around 6.5 X 10 to the 8th yr ago, a major source of relatively low abundance hydrogen was accreted by the Galactic disk, forming young high-velocity stars that do not partake of the age-abundance-kinematics relationships shown by other stellar groupings.