Chemodynamic subpopulations of the Carina dwarf galaxy
  We study the chemodynamical properties of the Carina dwarf spheroidal by
combining an intermediate spectroscopic resolution dataset of more than 900 red
giant and red clump stars, with high-precision photometry to derive the
atmospheric parameters, metallicities and age estimates for our targets. Within
the red giant branch population, we find evidence for the presence of three
distinct stellar sub-populations with different metallicities, spatial
distributions, kinematics and ages. As in the Fornax and Sculptor dwarf
spheroidals, the subpopulation with the lowest average metallicity is more
extended and kinematically hotter than all other populations. However, we
identify an inversion in the parallel ordering of metallicity, kinematics and
characteristic length scale in the two most metal rich subpopulations, which
therefore do not contribute to a global negative chemical gradient. Contrary to
common trends in the chemical properties with radius, the metal richest
population is more extended and mildly kinematically hotter than the main
component of intermediate metallicity. More investigations are required to
ascertain the nature of this inversion, but we comment on the mechanisms that
might have caused it.
