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The origin of distant B-type stars in the galactic halo

  • E. S. Conlon
  • R. J. H. McCausland
  • P. L. Dufton
  • F. P. Keenan
  • D. E. Holmgren
I. “Norman” Early-Type Stars
Part of the Lecture Notes in Physics book series (LNP, volume 401)

Abstract

Using model atmosphere analyses of high resolution optical spectra, we have identified a group of young B-type stars at large distances from the galactic plane. A study of the kinematics and evolutionary ages of these objects reveals two groups of stars: those that could have formed in the disc and travelled to their present locations in their lifetimes and those that could not. The kinematics of the first group are in agreement with results from N-body simulations of dynamical ejection from young galactic star clusters. For the stars that could not have formed in the disc, star formation in the halo via collisions within intermediate and high velocity clouds appears the most likely explanation.

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Copyright information

© Spriger-Verlag 1992

Authors and Affiliations

  • E. S. Conlon
    • 1
  • R. J. H. McCausland
    • 1
  • P. L. Dufton
    • 1
  • F. P. Keenan
    • 1
  • D. E. Holmgren
    • 1
  1. 1.Department of Pure and Applied PhysicsThe Queen's University of BelfastBelfastUK

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