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arXiv · 0912.3745

On the origin of the helium-rich population in the peculiar globular cluster Omega Centauri

D. Romano·M. Tosi·M. Cignoni·F. Matteucci·E. Pancino·M. Bellazzini
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Abstract

In this contribution we discuss the origin of the extreme helium-rich stars which inhabit the blue main sequence (bMS) of the Galactic globular cluster Omega Centauri. In a scenario where the cluster is the surviving remnant of a dwarf galaxy ingested by the Milky Way many Gyr ago, the peculiar chemical composition of the bMS stars can be naturally explained by considering the effects of strong differential galactic winds, which develop owing to multiple supernova explosions in a shallow potential well.

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D. Romano, M. Tosi, M. Cignoni, F. Matteucci, E. Pancino, M. Bellazzini. 2009-12-18. On the origin of the helium-rich population in the peculiar globular cluster Omega Centauri. https://doi.org/10.1017/s1743921310004114

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