Abstract
Recent discoveries of bimodal main sequences (MSs) associated with young clusters (with ages ≲1 Gyr) in the Magellanic Clouds have drawn a lot of attention. One of the prevailing formation scenarios attributes these split MSs to a bimodal distribution in stellar rotation rates, with most stars belonging to a rapidly rotating population. In this scenario, only a small fraction of stars populating a secondary blue sequence are slowly or non-rotating stars. Here, we focus on the blue MS in the young cluster NGC 1850. We compare the cumulative number fraction of the observed blue-MS stars to that of the high-mass-ratio binary systems at different radii. The cumulative distributions of both populations exhibit a clear anti-correlation, characterized by a highly significant Pearson coefficient of -0.97. Our observations are consistent with the possibility that blue-MS stars are low-mass-ratio binaries, and therefore their dynamical disruption is still ongoing. High-mass-ratio binaries, on the other hand, are more centrally concentrated.
Original language | English |
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Article number | 98 |
Pages (from-to) | 1-8 |
Number of pages | 8 |
Journal | Astrophysical Journal |
Volume | 859 |
Issue number | 2 |
DOIs | |
Publication status | Published - 1 Jun 2018 |
Bibliographical note
Copyright 2018 The American Astronomical Society. First published in the Astrophysical journal, 859(2), 98, 2018, published by IOP Publishing. The original publication is available at http://www.doi.org/10.3847/1538-4357/aabe26. Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.Keywords
- globular clusters: individual (NGC 1850)
- Hertzsprung-Russell and C-M diagrams
- Magellanic Clouds