A Study of the Color-magnitude Diagrams of Globular Clusters Hodge11, NGC1466, NGC2257

Abstract

Abstract:

Advanced stellar population synthesis（ASPS）was used to study the color- magnitude diagrams of globular clusters
Hodge11, NGC1466, and NGC2257, which were observed by the Hubble Space Telescope（HST）in the Large Magellanic Cloud.
Without the consideration of errors in the observation, the distance modulus, color excess, metallicity, age, star burst number, binary
fraction, and star formation history of clusters were determined through fitting. The result shows that the three star clusters are old（with
average age of more than 14 Gyr）, and of a metallicity Z of 0.000 3. All of them are shown to be like single stellar populations and have
about 60 percent binaries. It is shown that ASPS fits to the observations better than traditional models.

Key words: globular clusters, color-magnitude diagram, stellar population synthesis, binary star, parameters

CLC Number:

P154.1

Luo Qiping, Li Zhongmu. A Study of the Color-magnitude Diagrams of Globular Clusters Hodge11, NGC1466, NGC2257[J]. , 2016, 1(12): 26-29.

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