The SAMI Galaxy Survey: Spatially Resolved Metallicity and Ionization
  Mapping
  We present gas-phase metallicity and ionization parameter maps of 25
star-forming face-on spiral galaxies from the SAMI Galaxy Survey Data Release
1. Self-consistent metallicity and ionization parameter maps are calculated
simultaneously through an iterative process to account for the interdependence
of the strong emission line diagnostics involving ([OII]+[OIII])/H$\beta$ (R23)
and [OIII]/[OII] (O32). The maps are created on a spaxel-by-spaxel basis
because HII regions are not resolved at the SAMI spatial resolution. We combine
the SAMI data with stellar mass, star formation rate (SFR), effective radius
(R$_e$), ellipticity, and position angles (PA) from the GAMA survey to analyze
their relation to the metallicity and ionization parameter. We find a weak
trend of steepening metallicity gradient with galaxy stellar mass, with values
ranging from -0.03 to -0.20 dex/R$_e$. Only two galaxies show radial gradients
in ionization parameter. We find that the ionization parameter has no
significant correlation with either SFR, sSFR (specific star formation rate),
or metallicity. For several individual galaxies we find structure in the
ionization parameter maps suggestive of spiral arm features. We find a typical
ionization parameter range of $7.0 < \log(q) < 7.8$ for our galaxy sample with
no significant overall structure. An ionization parameter range of this
magnitude is large enough to caution the use of metallicity diagnostics which
have not considered the effects of a varying ionization parameter distribution.
