%0 Generic
%A Kaasinen, Melanie
%C Heidelberg
%D 2021
%F heidok:30283
%R 10.11588/heidok.00030283
%T The Molecular Interstellar Medium in Distant Galaxies
%U https://archiv.ub.uni-heidelberg.de/volltextserver/30283/
%X With the increased capabilities of sub-/millimeter facilities over the last decade it has become possible to observe the medium out of which most of the stars in today's Universe formed, the molecular interstellar medium in distant galaxies. In this thesis, I have tested what can be learnt from such observations, particularly of dust-continuum and CO emission. I compared the molecular gas masses inferred from observations of the ground transition of CO to those inferred from dust-continuum emission, finding that dust-continuum emission can be used to reliably infer the molecular gas content of massive star-forming galaxies at the peak epoch of star formation. However, by comparing the dust and CO emission at resolutions of a few kiloparsec, I found that dust-continuum emission is a poor tracer of molecular gas in the outskirts of typical star-forming galaxies at the same epoch. I also found that at least some distant star-forming  galaxies host large, centrally-concentrated molecular gas reservoirs.  Finally, I simulated molecular clouds with the aim of testing the impact of the Cosmic Microwave Background on observations of the emission from CO and atomic carbon in distant galaxies, highlighting the dominance of this background in the distant Universe.