Oral Presentation

Co-evolution of AGN and bulges: AGN are more common in real bulges than in pseudobulges

Author(s): Hassen Yesuf, Sandra Faber, David Koo, Joanna Woo, Joel Primack, Yifei Luo

Presenter: Hassen Yesuf (Kavli PKU/ Kavli IMPU)

We use bulge classifications of about 800 representative galaxies from Sloan Digital Sky Survey by Gadotti (2009), to classify galaxies into real bulges (classical or elliptical) or pseudo bulges using a machine learning algorithm, and structural and stellar population predictors that can easily be measured without resorting to careful bulge/bar/disc decomposition employed in our training sample. We classify about 50,000 face-on SDSS galaxies above stellar mass log M > 10.5 and redshift z < 0.07 into real bulges or pseudobulges with 93 % accuracy. Using the dust-corrected O III luminosity as an AGN accretion indicator, we find that AGNs have lower O III luminosity per black hole mass (Eddington ratios) in host galaxies with real bulges than in those with pseudobulges. The current specific accretion rates in pseudobulges are higher likely because they have more abundant gas to fuel their black holes