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We have recently identified a new radial migration mechanism resulting from the overlap of spiral and bar resonances in galactic disks. Here we confirm the efficiency of this mechanism in fully self-consistent, Tree-SPH simulations, as well as high-resolution pure N-body simulations. In all barred cases we clearly identify the effect of spiral-bar resonance overlap by measuring a bimodality in the changes of angular momentum in the disk, dL, whose maxima are near the bars corotation and outer Lindblad resonance. This contrasts with the smooth distribution of dL for a simulation with no stable bar present, where strong radial migration is induced by multiple spirals. The presence of a disk gaseous component appears to increase the rate of angular momentum exchange by about 20%. The efficiency of this mechanism is such that galactic stellar disks can extend to over 10 scale-lengths within 1-3 Gyr in both Milky Way size and low-mass galaxies (circular velocity ~100 km/s). We also show that metallicity gradients can flatten in less than 1 Gyr rendering mixing in barred galaxies an order of magnitude more efficient than previously thought.
Radial migration is an important process in the Galactic disk. A few open clusters show some evidence on this mechanism but there is no systematic study. In this work, we investigate the role of radial migration on the Galactic disk based on a large
We study how migration affects stars of a galaxy with a thin stellar disc and thicker stellar components. The simulated galaxy has a strong bar and lasting spiral arms. We find that the amplitude of the churning (change in angular momentum) is simila
It has been suggested that the high metallicity generally observed in active galactic nuclei (AGNs) and quasars originates from ongoing star formation in the self-gravitating part of accretion disks around the supermassive black holes. We designate t
By means of N-body simulations, we show that radial migration in galaxy disks, induced by bar and spiral arms, leads to significant azimuthal variations in the metallicity distribution of old stars at a given distance from the galaxy center. Metals d
The theoretical understanding of density waves in disk galaxies starts from the classical WKB perturbative analysis of tight-winding perturbations, the key assumption being that the potential due to the density wave is approximately radial. The above