V. Stanishev, M. Rodrigues, A. Mourao, H. Flores
We used the wide-field IFU spectrograph PMAS/PPAK at the 3.5m telescope of Calar Alto Observatory to observe six nearby spiral galaxies that hosted SNe Ia. Spatially resolved 2-dimensional maps of the properties of the ionized gas and the stellar populations were derived. Five of the observed galaxies have ongoing star formation rate of 1-5 M_sun/yr and mean stellar population ages ~5 Gyr. The sixth galaxy shows no star formation and has only ~12 Gyr old stellar population. All galaxies have stellar masses larger than 2E+10 M_sun and metallicities above solar. Four galaxies show negative radial metallicity gradients of the ionized gas up to -0.058 dex/kpc and one has nearly uniform metallicity with a possible small positive slope. The stellar components show shallower negative metallicity gradients up to -0.03 dex/kpc. We find no clear correlation between the properties of the galaxy and those of the supernovae, a fact that can be due to the small ranges spanned by the galaxy parameters. However we note that the Hubble residuals are on average positive while negative Hubble residuals are expected for SNe Ia in massive hosts such as the galaxies in our sample. In conclusion, IFU spectroscopy on 4-m telescopes is a viable technique to study host galaxies of nearby SNe Ia. It allows to correlate the supernova properties with the properties of their host galaxies at the projected positions of the supernovae. Our current sample of six galaxies is too small to draw conclusions about the SN Ia progenitors or correlations with the galaxy properties, but the ongoing CALIFA IFU survey will provide a solid basis to further exploit this technique and improve our understanding of SNe Ia as cosmological standard candles.
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http://arxiv.org/abs/1205.5183
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