Chemical Evolution in the Large Magellanic Cloud

Abstract

We present a new input parameter set of the Pagel model (Pagel & Tautvai$\rm \breve{s}$ien$\rm \dot{e}$ 1998) for the Large Magellanic Cloud (LMC) in order to reproduce the observations, including the star formation rate (SFR) history. It is concluded that the probability for (3-8)$M_{\odot}$ stars to explode as SNe Ia has to be quite high ($\sim 0.17$) in the LMC. As a result, a steep initial mass function (IMF) slope and existence of the outflow are not needed in order to attain the low [O/Fe] ratio in the LMC. As for the current supernova ratio, a high ratio ($\sim 1.3$) is concluded by the new parameter set, which is consistent with the recent X-ray observations.Comment: 20 pages, gzipped tar file including LaTeX text and 8 postscript figures. submitted to Publication of the Astronomical Society of Japa