"Fuelling Black Hole Growth Through Large Scale Bars"

Abstract

Despite most supermassive black hole (SMBH) growth occurring via merger-free processes, the underlying mechanisms driving this secular evolution are poorly understood. I will present my work highlighting the role that both strong and weak large-scale galactic bars play in mediating this growth, by analysing the active galactic nucleus (AGN) presence. Strongly barred galaxies have a higher fraction of AGN than weakly barred galaxies, which in turn have a higher fraction than unbarred galaxies. Thus, while bars are not required in order to grow an SMBH in a disc galaxy, large-scale galactic bars appear to facilitate AGN fuelling, and the presence of a strong bar makes a disc galaxy more than twice as likely to host an AGN than an unbarred galaxy at all galaxy stellar masses and colours. I will then present more recent work that separates the contribution of the bar and the contribution of the galactic bulge to AGN presence.