The Milky Way’s central region (the central molecular zone or CMZ) contains a modern astrophysical enigma. Despite its impressive reservoir of fuel for star formation, hosting 80% of all the high density gas in the Milky Way, the CMZ appears to be forming far fewer stars than we would expect. The Galactic Center hosts one of the most extreme physical environments in the Galaxy, where the high density gas that fuels star formation is twisted and heated by powerful turbulence. This extraordinary environment is an excellent laboratory to push our theories of star formation to their limits.
The CMZoom survey was designed to take a complete look at the high density clouds of the CMZ and generate a catalog of all possible sites of high mass star formation in the Galactic Center. Massive stars should form in the densest clumps of molecular hydrogen, so by completely surveying all high column density regions in the innermost ~300pc of the Galaxy, we can construct a census of all possible sites of high mass star formation!
To accomplish this, the CMZoom team carried out a Large Program with the Submillimeter Array, with 550 hours of observations mapping all material above a column density of 1023 N(H2). Using the 1.3mm dust continuum emission, we constructed a catalog of compact, bright sources and characterized their physical properties. The survey revealed a startling lack of compact dust emission across most of the CMZ, with the vast majority of fuel ready to form stars contained within already well known stellar nurseries, like Sgr B2. Still, the completeness of the survey lets us constrain the future potential for star formation in the CMZ, which we find largely to be in agreement with past estimates.
Future work is underway to expand our understanding of the spectral properties of these sources. What molecular lines are associated with these sources? Which sources are gravitationally bound? Are there protostellar outflows associated with any of them? Additionally, we are exploring the star forming properties of all of these CMZoom catalog sources to better constrain the upcoming star formation rate of the CMZ using the wealth of far infrared surveys toward the Galactic Center. Stay tuned for further research!