A New Analysis of RR Lyrae Kinematics in the Solar Neighborhood

  title={A New Analysis of RR Lyrae Kinematics in the Solar Neighborhood},
  author={John C. Martin and Heather L. Morrison},
  journal={The Astronomical Journal},
  pages={1724 - 1735}
Full space velocities are computed for a sample of 130 nearby RR Lyrae variables using both ground-based and Hipparcos proper motions. In many cases proper motions for the same star from multiple sources have been averaged to produce approximately a factor of 2 improvement in the transverse space velocity errors. In most cases, this exceeds the accuracy attained using Hipparcos proper motions alone. The velocity ellipsoids computed for halo and thick-disk samples are in agreement with those… 

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