CARBON ABUNDANCES IN THE LMC GLOBULAR-CLUSTER NGC-1818

From medium-resolution spectra (similar to 5 Angstrom) of 5 red superg iants in the globular cluster NGC 1818 of the Large Magellanic Cloud, we have derived their metallicities through a comparison to a grid of 380 synthetic spectra (Cayrel et al. 1991). The carbon abundances were then derived by computing synthetic spectra in the G-band region. A m ean metallicity for the 5 stars is [Fe/H] approximate to -0.9. The mea n carbon abundance is epsilon(C) = 7.9 for 4 stars, and a lower value of epsilon(C) = 7.2 for the star B26, for which a convective mixing, o r exchange of material with a companion has possibly occurred.