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Galactic abundance gradients from ob-type stars in young clusters and associations

  • A. Fitzsimmons
  • P. J. F. Brown
  • P. L. Dufton
  • W. R. J. Rolleston
I. “Norman” Early-Type Stars
Part of the Lecture Notes in Physics book series (LNP, volume 401)

Abstract

High-resolution spectra of main sequence B-type stars in young galactic clusters have been analysed using LTE and (where appropriate) non-LTE model atmosphere calculations. A re-analysis of the O II data from 11 clusters indicates that within 2 kpc of the sun there appears to be no obvious abundance gradient with respect to galactocentric distance. However, the cluster Dolidze 25 lying at R g = 13.5 kpc has been found to be oxygen deficient, implying that the abundance gradient may be non-linear. A comparison with studies of H II regions indicates that within the uncertainties the two methods yield consistent abundances. We are currently analysing clusters with 10 kpc ≤ Ry ≤ 12kpc and will shortly be obtaining data on clusters with R g ≤ 16kpc.

Keywords

Solar Neighbourhood Oxygen Abundance Galactocentric Distance Young Cluster Abundance Gradient 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag 1992

Authors and Affiliations

  • A. Fitzsimmons
    • 1
  • P. J. F. Brown
    • 1
  • P. L. Dufton
    • 1
  • W. R. J. Rolleston
    • 1
  1. 1.Department of Pure and Applied PhysicsQueens University of BelfastBelfastUK

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