Speaker
Annika Franeck
(Universität zu Köln)
Description
C+ fine structure emission has recently been studied with Herschel and Sofia.
The results promote C+ as a tracer for star formation in galactic discs or CO-dark molecular gas. Furthermore, the scale height of the C+ emission in the Milky Way and in distant galaxies is not well understood. Does it trace the disc dynamics?
Using RADMC-3D, we post-process three-dimensional, magneto-hydrodynamical simulations of pieces of stratified, galactic discs with a solar-neighborhood gas surface densityof 10 Msun/pc^2 to compute synthetic C+ emission maps. Excluding the emission from photon-dominated regions, we find that most of the C+ emission in our model originates from the surfaces of cold molecular clouds. These contribute a narrow but prominent component to the C+ maps.
Moreover, we see a broad component distributed around the midplane, which stems from warmer gas.
We compare simulations including different physics (with/without gas self-gravity, or with/without magnetic fields) and different supernova rates, and study the influence on the C+ scale height. We find that the C+ scale height is highly variable, as the emission traces the onset of galactic outflows.