Complete ejection of OB stars from very young star clusters and the formation of multiple populations

  title={Complete ejection of OB stars from very young star clusters and the formation of multiple populations},
  author={Long Wang and Pavel Kroupa and Tereza Jeř{\'a}bkov{\'a}},
  journal={Monthly Notices of the Royal Astronomical Society},
Recently, three stellar sequences separated in age by about 1 Myr were discovered in the Orion Nebula Cluster (ONC; Beccari et al. 2017). Kroupa et al. (2018) suggest that such small dense subpopulations eject all their OB stars via the decay of unstable few-body systems such that the gas can recombine and form new stars. This explains the multisequence phenomenon without introducing an extra mechanism into star formation theory. In this work, we apply the recently updated primordial binary… 

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