Dating compact star clusters in the Small Magellanic Cloud by means of integrated spectra

We present flux-calibrated spectra in the optical range for 11 compact Small Magellanic Cloud (SMC) star clusters, two of which are unstudied objects. Cluster reddening values are estimated by interpolation between the extinction maps of Burstein and Heiles (1982). We used two different procedures to derive cluster ages: (i) template matching, and (ii) equivalent width (EW) method, in which diagnostic diagrams involving the sum of EWs of selected spectral lines were employed together with their calibrations with age and metallicity. A reasonably good agreement between ages derived from both procedures was found. The resulting foreground E(B-V) values are in the small range 0.00 < E(B-V) < 0.12, while ages vary from ~ 4 Myr in Bruck 50 to ~ 400 Myr in IC 1641. The present data constitute a spectral library at the metallicity level of SMC clusters.