Multiple populations in Galactic globular clusters: a survey in the Strömgren system

J. Alonso-García; M. Catelan; P. Amigo; C. Cortés; C. A. Kuehn; F. Grundahl; G. López; R. Salinas; H. A. Smith; P. B. Stetson; A. V. Sweigart; A. A. R. Valcarce; M. Zoccali

arXiv · 1301.2772

Multiple populations in Galactic globular clusters: a survey in the Strömgren system

J. Alonso-García·M. Catelan·P. Amigo·C. Cortés·C. A. Kuehn·F. Grundahl·G. López·R. Salinas·H. A. Smith·P. B. Stetson·A. V. Sweigart·A. A. R. Valcarce·M. Zoccali

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Abstract

We are coming to believe that stellar populations in globular clusters are not as simple as they were once thought to be. A growing amount of photometric and spectroscopic evidence shows that globular clusters host at least two different stellar populations. In our contribution to these proceedings we present the first results of a survey we are conducting to look for the presence of multiple populations in a significant number of Galactic globular clusters, using the Strömgren system. We intend to photometrically separate these populations and characterize their radial distributions and extensions.

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J. Alonso-García, M. Catelan, P. Amigo, C. Cortés, C. A. Kuehn, F. Grundahl, G. López, R. Salinas, H. A. Smith, P. B. Stetson, A. V. Sweigart, A. A. R. Valcarce, M. Zoccali. 2013-01-13. Multiple populations in Galactic globular clusters: a survey in the Strömgren system. https://arxiv.org/abs/1301.2772

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