UNIGE document Scientific Article
previous document  unige:54918  next document
add to browser collection

Stellar diffusion in barred spiral galaxies

Chiappini, Cristina
Published in Astronomy & astrophysics. 2011, vol. 534, A75
Abstract We characterize empirically the radial diffusion of stars in the plane of a typical barred disk galaxy by calculating the local spatial diffusion coefficient and diffusion time-scale for bulge-disk-halo N-body self-consistent systems which initially differ in the Safronov-Toomre-Q_T parameter. We find different diffusion scenarios that depend on the bar strength and on the degree of instability of the disk. Marginally stable disks, with Q_T sim 1, have two families of bar orbits with different values of angular momentum and energy, which determine a large diffusion in the corotation region. In hot disks, Q_T> 1, stellar diffusion is reduced with respect to the case of marginally stable disks. In cold models, we find that spatial diffusion is not constant in time and strongly depends on the activity of the bar, which can move stars all over the disk recurrently. We conclude that to realistically study the impact of radial migration on the chemical evolution modeling of the Milky Way the role of the bar has to be taken into account.
Keywords Methods: numericalGalaxy: bulgeGalaxies: kinematics and dynamicsGalaxies: spiralGalaxies: stellar contentGalaxy: disk
Full text
(ISO format)
BRUNETTI, Maura, CHIAPPINI, Cristina, PFENNIGER, Daniel. Stellar diffusion in barred spiral galaxies. In: Astronomy & astrophysics, 2011, vol. 534, p. A75. doi: 10.1051/0004-6361/201117566 https://archive-ouverte.unige.ch/unige:54918

513 hits



Deposited on : 2015-03-30

Export document
Format :
Citation style :