Metallicity Gradients and Gas Flows in Galaxy Pairs
  We present the first systematic investigation into the metallicity gradients
in galaxy close pairs. We determine the metallicity gradients for 8 galaxies in
close pairs using HII region metallicities obtained with high signal-to-noise
multi-slit observations with the Keck LRIS Spectrograph. We show that the
metallicity gradients in close pairs are significantly shallower than gradients
in isolated spiral galaxies such as the Milky Way, M83, and M101. These
observations provide the first solid evidence that metallicity gradients in
interacting galaxies are systematically different from metallicity gradients in
isolated spiral galaxies. Our results suggest that there is a strong
relationship between metallicity gradients and the gas dynamics in galaxy
interactions and mergers.
