1 research outputs found
The most luminous, merger-free AGN show only marginal correlation with bar presence
The role of large-scale bars in the fuelling of active galactic nuclei (AGN)
is still debated, even as evidence mounts that black hole growth in the absence
of galaxy mergers cumulatively dominated and may substantially influence disc
(i.e., merger-free) galaxy evolution. We investigate whether large-scale
galactic bars are a good candidate for merger-free AGN fuelling. Specifically,
we combine slit spectroscopy and Hubble Space Telescope imagery to characterise
star formation rates (SFRs) and stellar masses of the unambiguously
disc-dominated host galaxies of a sample of luminous, Type-1 AGN with 0.02 < z
0.024. After carefully correcting for AGN signal, we find no clear difference
in SFR between AGN hosts and a stellar mass-matched sample of galaxies lacking
an AGN (0.013 < z < 0.19), although this could be due to a small sample size
(n_AGN = 34). We correct for SFR and stellar mass to minimise selection biases,
and compare the bar fraction in the two samples. We find that AGN are
marginally (1.7) more likely to host a bar than inactive galaxies, with
AGN hosts having a bar fraction, fbar = 0.59^{+0.08}_{-0.09} and inactive
galaxies having a bar fraction fbar = 0.44^{+0.08}_{-0.09}. However, we find no
further differences between SFR- and mass-matched AGN and inactive samples.
While bars could potentially trigger AGN activity, they appear to have no
further, unique effect on a galaxy's stellar mass or SFR.Comment: 15 pages (9 figures). Accepted for publication in MNRA