A Correlation between Star Formation Rate and Average Black Hole Accretion in Star-forming Galaxies (Proceeding of IAUS304: Multiwavelength AGN Surveys and Studies)

TL;DR

This study demonstrates a strong correlation between star formation rates and average black hole accretion in star-forming galaxies, suggesting linked growth over galaxy evolution timescales, based on Herschel and Chandra observations.

Contribution

It provides new evidence of a linear correlation between SMBH accretion and star formation when averaging over galaxy populations, highlighting their co-evolution.

Findings

Strong correlation between star formation rate and SMBH accretion in SF galaxies.

Weak correlation observed for individual AGN due to variability.

Averaged data shows a linear relationship indicating co-evolution.

Abstract

We present the results of recent studies on the co-evolution of galaxies and the supermassive black holes (SMBHs) using Herschel far-infrared and Chandra X-ray observations in the Bo\"otes survey region. For a sample of star-forming (SF) galaxies, we find a strong correlation between galactic star formation rate and the average SMBH accretion rate in SF galaxies. Recent studies have shown that star formation and AGN accretion are only weakly correlated for individual AGN, but this may be due to the short variability timescale of AGN relative to star formation. Averaging over the full AGN population yields a strong linear correlation between accretion and star formation, consistent with a simple picture in which the growth of SMBHs and their host galaxies are closely linked over galaxy evolution time scales.