The Carina Nebula and Gum 31 molecular complex III: The distribution of
  the 1-3 GHz radio continuum across the whole nebula
  We report the most detailed $1-3$ GHz radio continuum emission map of the
nearest region of massive star formation, the Carina Nebula. As part of a large
program with the Australia Telescope Compact Array, we have covered $\sim$ 12
deg$^2$, achieving an angular resolution of $\sim$ 16 arcsec, representing the
largest and most complete map of the radio continuum to date. Our continuum map
shows a spectacular and complex distribution of emission across the nebula,
with multiple structures such as filaments, shells, and fronts across a wide
range of size scales. The ionization fronts have advanced far into the southern
and northern region of the Galactic Plane, as fronts are clearly detected at
distances $\sim$ 80 pc from the stellar clusters in the center. We estimated an
ionization photon luminosity $Q_\mathrm{H}=(7.8 \pm 0.8) \times 10^{50}$
s$^{-1}$ which corresponds to $\sim 85\%$ of the total value obtained from
stellar population studies. Thus, approximately $15\%$ of the ionizing flux has
escaped from the nebula into the diffuse Galactic Interstellar Medium.
Comparison between radio continuum and the hydrogen atomic and molecular gas
maps offers a clear view of the bipolar outflow driven by the energy released
by the massive stellar clusters that also affects the fraction of molecular gas
across the nebula. Comparison between 8$\mu$m and 70$\mu$m emission maps and
the radio continuum reveals how the hot gas permeates through the molecular
cloud, shapes the material into features such as pillars, small shells and
arc-like structures, and ultimately, escapes.
