SIMBAD references

An evolutionary model is developed for the Large Magellanic Cloud (LMC), taking into account constraints in the star formation history imposed by recent data on color-magnitude diagrams of field stars. The present model has a ``closed'' geometry, since the onset of a galactic wind in the early phases of the LMC is questioned. The code followed the evolution of several primary elements such as O, Mg, Si, S, Ar, Ca, and Fe, including the contribution of both Type Ia and Type II supernovae to the chemical enrichment. An initial mass function steeper than that in the solar neighborhood seems to be necessary to produce negative [O/Fe] ratios, but this conclusion depends on the adopted yields and star formation history. The signature of the past enhanced star formation period, 2-3 Gyr ago, is clearly seen in the behavior of the oxygen and sulfur evolution, representing a possible observational test for the proposed model.