We examine the connection between galaxy mergers and the triggering of active galactic nuclei (AGNs) using a sample of 614 type 1 AGNs at z<0.07, along with a control sample of inactive galaxies matched to the AGNs for comparison. We use tidal features, detected in deep images from the DESI Legacy Imaging Survey, as direct evidence of recent mergers. We find that the fraction of type 1 AGN hosts with tidal features (f_T_) is higher for AGNs with higher luminosities and (to a lesser extent) more massive black holes. Specifically, f_T_ rapidly increases from 0.05+/-0.03 to 0.75+/-0.13 as the luminosity of the [OIII] {lambda}5007 emission line (L_[OIII]), an indicator for bolometric AGN luminosity, increases in the range of 10^39.5^<~L[OIII]/(erg/s)<~10^42.5. In addition, f_T increases from 0.13+/-0.03 to 0.43+/-0.09 as black hole mass (M_BH) increases in the range of 10^6.0<~M_BH_/M_{sun}<~10^8.5. The fraction f_T also increases with the Eddington ratio, although the trend is less significant compared to that with L_[OIII] and M_BH. The excess of f_T_, defined as the ratio of f_T_ for AGNs to that of their matched inactive counterparts, exhibits similar trends, primarily increasing with L_[OIII] and weakly with M_BH. Our results indicate that, in the local universe, galaxy mergers are the predominant triggering mechanism for high-luminosity AGNs, whereas they play a lesser role in the triggering lower-luminosity AGNs. Additionally, strong events, such as galaxy mergers, may be more necessary to activate massive black holes in more massive galaxies due to their lower gas fraction.

Cone search capability for table J/A+A/704/A211/table1 (Properties of type 1 AGNs)