A halo blue straggler on a highly eccentric retrograde orbit

  title={A halo blue straggler on a highly eccentric retrograde orbit},
  author={Alfred Tillich and Norbert Przybilla and Ralf-Dieter Scholz and Ulrich Heber},
  journal={Astronomy and Astrophysics},
Context. Blue stragglers, which are stars that appear to be younger than they should be, are an important population of unusual stars in both stellar clusters and the halo field of the Galaxy. Most formation scenarios evoke either stellar collisions or binary stars that transfer mass or merge. Aims. We investigate high-velocity stars in the Galactic halo and perform a spectral and kinematical analysis to shed light on their nature and origin. Here we report that SDSSJ130005.62+042201.6 (J1300… 

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