September 2016

merger_fraction_minor_vs_major

How important are minor mergers for triggering AGN activity?

The figure shows the merger fraction of minor mergers divided by the one of major mergers, plotted versus the AGN luminosity at different redshifts for one of the Magneticum simulations (500Mpc/hr). The arrows on the left are all inactive galaxies. Since the fraction is roughly the same for AGN than for inactive galaxies, minor mergers are equally important as major mergers for triggering AGN activity! Only for very luminous AGN major mergers are somewhat more important than minor mergers, especially at low redshifts.