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A catalogue of Large Magellanic Cloud star clusters observed in the Washington photometric system

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 نشر من قبل Tali Palma
 تاريخ النشر 2015
  مجال البحث فيزياء
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The main goal of this study is to compile a catalogue including the fundamental parameters of a complete sample of 277 star clusters (SCs) of the Large Magellanic Cloud (LMC) observed in the Washington photometric system, including 82 clusters very recently studied by us. All the clusters parameters such as radii, deprojected distances, reddenings, ages and metallicities have been obtained by appyling essentially the same procedures which are briefly described here. We have used empirical cumulative distribution functions to examine age, metallicity and deprojected distance distributions for different cluster subsamples of the catalogue. Our new sample made up of 82 additional clusters recently studied by us represents about a 40% increase in the total number of LMC SCs observed up to now in the Washington photometric system. In particular, we report here the fundamental parameters obtained for the first time for 42 of these clusters. We found that single LMC SCs are typically older than multiple SCs. Both single and multiple SCs exhibit asymmetrical distributions in log (age). We compared cluster ages derived through isochrone fittings obtained using different models of the Padova group. Although $t_G$ and $t_B$ ages obtained using isochrones from Girardi et al. (2002) and Bressan et al. (2012), respectively, are consistent in general terms, we found that $t_B$ values are not only typically larger than $t_G$ ages but also that Bressan et al.s age uncertainties are clearly smaller than the corresponding Girardi et al. values.



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