The Abundance Pattern of O, Ne, Mg, and Fe in the Interstellar Medium of
  S0 Galaxy NGC 4382 Observed with Suzaku
  We derived O, Ne, and Mg abundances in the interstellar medium (ISM) of a
relatively isolated S0 galaxy, NGC 4382, observed with the Suzaku XIS
instruments and compared the O/Ne/Mg/Fe abundance pattern to those of the ISM
in elliptical galaxies. The derived temperature and Fe abundance in the ISM are
about 0.3 keV and 0.6--2.9 solar, respectively. The abundance ratios are
derived with a better accuracy than the abundances themselves: O/Fe, Ne/Fe, and
Mg/Fe ratios are 0.3, 0.7, and 0.6, respectively, in solar units. The O/Fe
ratio is smaller than that of the ISM in elliptical galaxies, NGC 720, NGC
1399, NGC 1404, and NGC 4636, observed with Suzaku. Since O, Ne, and Mg are
predominantly synthesized by supernovae (SNe) of type II, the observed
abundance pattern indicates that the contribution of SN Ia products is higher
in the S0 galaxy than in the elliptical galaxies Since the hot ISM in
early-type galaxies is an accumulation of stellar mass and SN Ia products, the
low O/Fe ratio in the ISM of NGC 4382 reflects a higher rate of present SNe Ia,
or stars containing more SN Ia products than those in elliptical galaxies.
