Contributed Talk - Splinter SMBHs

Wednesday, 23 September 2020, 15:10   (virtual room K)

The co-evolution of star-forming galaxies and their supermassive black holes across cosmic time

Joao Calhau
Lancaster University

We probe the relation between the star formation rate (SFR) and black hole acretion rate (BHAR) for star-forming galaxies across cosmic time from z = 0.4−6, using the HiZELS and SC4K surveys to select a large sample of line-emitting star-forming galaxies (∼ 700 Ha emitters - HAEs - at z=0.4−2 for HiZELS and ∼ 4000 Lyman-a emitters - LAEs - at z=2−6 for SC4K). We use stacking and SED fitting techniques, as well as direct source extraction on the publicly available data in the X-rays, radio and FIR bands for the COSMOS field, and estimate the BHARs and SFRs of star-forming galaxies. We find no correlations between the radio emission and Lya but discover that the X-ray BHAR of star forming galaxies follows the evolution of SFR up to at least z = 3, with practically no delay between the two. We also conclude that LAEs are comprised of different populations: an AGN population, where Lya becomes an accretion indicator, and a star-forming population that is detected in the radio but remains unseen in the X-rays.