English

Spectral Types of Field and Cluster O-Stars

Astrophysics 2009-11-10 v2

Abstract

The recent catalog of spectral types of Galactic O-type stars by Mai'z-Apella'niz et al. has been used to study the differences between the frequencies of various subtypes of O-type stars in the field, in OB associations and among runaway stars. At a high level of statistical significance the data show that O-stars in clusters and associations have earlier types (and hence presumably larger masses and/or younger ages) than those that are situated in the general field. Furthermore it is found that the distribution of spectral subtypes among runaway O-stars is indistinguishable from that among field stars, and differs significantly from that of the O-type stars that are situated in clusters and associations. The difference is in the sense that runaway O-stars, on average, have later subtypes than do those that are still located in clusters and associations.

Keywords

Cite

@article{arxiv.astro-ph/0406590,
  title  = {Spectral Types of Field and Cluster O-Stars},
  author = {Sidney van den Bergh},
  journal= {arXiv preprint arXiv:astro-ph/0406590},
  year   = {2009}
}

Comments

To be published in the October 2004 issue of the Astronomical Journal Included Figure 1, page 9