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Determination of reddening and age for ten Large Magellanic Cloud star clusters from integrated spectroscopy

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 نشر من قبل Tali Palma
 تاريخ النشر 2016
  مجال البحث فيزياء
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We present flux-calibrated integrated spectra in the optical range (3700-6800 AA) obtained at Complejo Astronomico El Leoncito (CASLEO, Argentina) for a sample of 10 concentrated star clusters belonging to the Large Magellanic Cloud (LMC). No previous data exist for two of these objects (SL 142 and SL 624), while most of the remaining clusters have been only poorly studied. We derive simultaneously foreground $E(B-V)$ reddening values and ages for the cluster sample by comparing their integrated spectra with template LMC cluster spectra and with two different sets of simple stellar population models. Cluster reddening values and ages are also derived from both available interstellar extinction maps and by using diagnostic diagrams involving the sum of equivalent widths of some selected spectral features and their calibrations with age, respectively. For the studied sample, we derive ages between 1 Myr and 240 Myr. In an effort to create a spectral library at the LMC metallicity level with several clusters per age range, the cluster sample here presented stands out as a useful complement to previous ones.



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