Emission Line Velocity, Metallicity and Extinction Maps of the Large Magellanic Cloud

We measure the properties of optical emission lines in multiple locations across the Large Magellanic Cloud (LMC) using the Australian National University 2.3-metre telescope and the WiFeS integral field spectrograph. From these measurements we interpolate maps of the gas phase metallicity, extinction, Halpha radial velocity, and Halpha velocity dispersion across the LMC. The LMC metallicity maps show a complex structure that cannot be explained by a simple radial gradient. The bright HII region 30 Doradus stands out as a region of high extinction. The Halpha and HI gas radial velocities are mostly consistent except for a region to the south and east of the LMC centre. The Halpha velocity dispersion is almost always higher than the HI velocity dispersion, except in the region that shows the divergence in radial velocity, where the HI velocity dispersion is greater than the Halpha velocity dispersion. This suggests that the HI gas is diverging from the stellar radial velocity, perhaps as a result of inflow or outflow of HI gas. The study of dwarf galaxies like the LMC is important as they are the building blocks of larger galaxies like our own Milky Way. The maps provided in this work show details not accessible in the study of more distant dwarf galaxies.
Comment: Accepted by MNRAS