Targeted observations of the past decade have uncovered a population of galaxies with extraordinarily buried galactic nuclei. These nuclei are compact and energetic, but we do not yet know if they are powered by extreme star formation or by the growth of a supermassive black hole. Furthermore, it was unclear how common these Compact Obscured Nuclei (CONs) are – are they curiosities or an important phase of galaxy evolution?
To address this question, we launched the CONquest survey to perform a systematic search for these extreme nuclei. After a series of observations with the Atacama Large Millimeter Array on a sample of galaxies, we have established that 30% of Ultraluminous infrared galaxies and 21% of luminous infrared galaxies harbor CONs in their centers. In contrast we found no CONs in a lower-luminosity set of galaxies. The findings are detailed in “CON-quest: Searching for the most obscured galaxy nuclei” (Falstad+), that has been accepted for publication in Astronomy & Astrophysics. A preprint is available.