Properties of the Hot Gas Outflow of NGC 253

We analyze image and spectral data from the Chandra X-ray Observatory of the nearby edge-on starburst galaxy NGC 253 to constrain various properties of the hot phase of its outflow. We focus our analysis on the -1 kpc to 0.5 kpc area along the outflow and define several regions for spectral extraction where we find best-fit temperatures and metal abundances. We find that the temperatures and electron densities peak in the center of the outflow and decrease with distance. These temperature and density profiles are in disagreement with an adiabatic spherically expanding starburst model and demonstrate the need for models to account for mass loading and non-spherical outflow geometry. Our metal abundances of O, Ne, Mg, Si, S, and Fe all peak in the center of outflow and decrease with distance with the exception of Ne that maintains a flat distribution throughout the outflow. In our regions we also detect emission from charge exchange and find it has a significant contribution to the total X-ray emission.