Article

On the origin of complex stellar populations in star clusters

Proceedings of the International Astronomical Union 09/2007; DOI: 10.1017/S1743921308015330
Source: arXiv

ABSTRACT The existence of complex stellar populations in some star clusters challenges the understanding of star formation. E.g. the ONC or the sigma Orionis cluster host much older stars than the main bulk of the young stars. Massive star clusters (omega Cen, G1, M54) show metallicity spreads corresponding to different stellar populations with large age gaps. We show that (i) during star cluster formation field stars can be captured and (ii) very massive globular clusters can accrete gas from a long-term embedding inter stellar medium and restart star formation. Comment: 2 pages, 3 figures, To be published in the proceedings of IAUS246 "Dynamical Evolution of Dense Stellar Systems", ed. E. Vesperini (Chief Editor), M. Giersz, A. Sills

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